# Copyright (c) 2010-2012 OpenStack Foundation # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or # implied. # See the License for the specific language governing permissions and # limitations under the License. import copy import errno import mock import operator import os import unittest import six.moves.cPickle as pickle from array import array from collections import Counter, defaultdict from math import ceil from tempfile import mkdtemp from shutil import rmtree import random import uuid from six.moves import range from swift.common import exceptions from swift.common import ring from swift.common.ring import utils from swift.common.ring.builder import MAX_BALANCE class TestRingBuilder(unittest.TestCase): def setUp(self): self.testdir = mkdtemp() def tearDown(self): rmtree(self.testdir, ignore_errors=1) def _partition_counts(self, builder, key='id'): """ Returns a dictionary mapping the given device key to (number of partitions assigned to that key). """ return Counter(builder.devs[dev_id][key] for part2dev_id in builder._replica2part2dev for dev_id in part2dev_id) def _get_population_by_region(self, builder): """ Returns a dictionary mapping region to number of partitions in that region. """ return self._partition_counts(builder, key='region') def test_init(self): rb = ring.RingBuilder(8, 3, 1) self.assertEqual(rb.part_power, 8) self.assertEqual(rb.replicas, 3) self.assertEqual(rb.min_part_hours, 1) self.assertEqual(rb.parts, 2 ** 8) self.assertEqual(rb.devs, []) self.assertFalse(rb.devs_changed) self.assertEqual(rb.version, 0) def test_overlarge_part_powers(self): expected_msg = 'part_power must be at most 32 (was 33)' with self.assertRaises(ValueError) as ctx: ring.RingBuilder(33, 3, 1) self.assertEqual(str(ctx.exception), expected_msg) def test_insufficient_replicas(self): expected_msg = 'replicas must be at least 1 (was 0.999000)' with self.assertRaises(ValueError) as ctx: ring.RingBuilder(8, 0.999, 1) self.assertEqual(str(ctx.exception), expected_msg) def test_negative_min_part_hours(self): expected_msg = 'min_part_hours must be non-negative (was -1)' with self.assertRaises(ValueError) as ctx: ring.RingBuilder(8, 3, -1) self.assertEqual(str(ctx.exception), expected_msg) def test_deepcopy(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sdb1'}) # more devices in zone #1 rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sdc1'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sdd1'}) rb.rebalance() rb_copy = copy.deepcopy(rb) self.assertEqual(rb.to_dict(), rb_copy.to_dict()) self.assertIsNot(rb.devs, rb_copy.devs) self.assertIsNot(rb._replica2part2dev, rb_copy._replica2part2dev) self.assertIsNot(rb._last_part_moves, rb_copy._last_part_moves) self.assertIsNot(rb._remove_devs, rb_copy._remove_devs) self.assertIsNot(rb._dispersion_graph, rb_copy._dispersion_graph) def test_get_ring(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.remove_dev(1) rb.rebalance() r = rb.get_ring() self.assertIsInstance(r, ring.RingData) r2 = rb.get_ring() self.assertIs(r, r2) rb.rebalance() r3 = rb.get_ring() self.assertIsNot(r3, r2) r4 = rb.get_ring() self.assertIs(r3, r4) def test_rebalance_with_seed(self): devs = [(0, 10000), (1, 10001), (2, 10002), (1, 10003)] ring_builders = [] for n in range(3): rb = ring.RingBuilder(8, 3, 1) idx = 0 for zone, port in devs: for d in ('sda1', 'sdb1'): rb.add_dev({'id': idx, 'region': 0, 'zone': zone, 'ip': '127.0.0.1', 'port': port, 'device': d, 'weight': 1}) idx += 1 ring_builders.append(rb) rb0 = ring_builders[0] rb1 = ring_builders[1] rb2 = ring_builders[2] r0 = rb0.get_ring() self.assertIs(rb0.get_ring(), r0) rb0.rebalance() # NO SEED rb1.rebalance(seed=10) rb2.rebalance(seed=10) r1 = rb1.get_ring() r2 = rb2.get_ring() self.assertIsNot(rb0.get_ring(), r0) self.assertNotEqual(r0.to_dict(), r1.to_dict()) self.assertEqual(r1.to_dict(), r2.to_dict()) def test_rebalance_part_on_deleted_other_part_on_drained(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10005, 'device': 'sda1'}) rb.rebalance(seed=1) # We want a partition where 1 replica is on a removed device, 1 # replica is on a 0-weight device, and 1 on a normal device. To # guarantee we have one, we see where partition 123 is, then # manipulate its devices accordingly. zero_weight_dev_id = rb._replica2part2dev[1][123] delete_dev_id = rb._replica2part2dev[2][123] rb.set_dev_weight(zero_weight_dev_id, 0.0) rb.remove_dev(delete_dev_id) rb.rebalance() def test_set_replicas(self): rb = ring.RingBuilder(8, 3.2, 1) rb.devs_changed = False rb.set_replicas(3.25) self.assertTrue(rb.devs_changed) rb.devs_changed = False rb.set_replicas(3.2500001) self.assertFalse(rb.devs_changed) def test_add_dev(self): rb = ring.RingBuilder(8, 3, 1) dev = {'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000} dev_id = rb.add_dev(dev) self.assertRaises(exceptions.DuplicateDeviceError, rb.add_dev, dev) self.assertEqual(dev_id, 0) rb = ring.RingBuilder(8, 3, 1) # test add new dev with no id dev_id = rb.add_dev({'zone': 0, 'region': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 6200}) self.assertEqual(rb.devs[0]['id'], 0) self.assertEqual(dev_id, 0) # test add another dev with no id dev_id = rb.add_dev({'zone': 3, 'region': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 6200}) self.assertEqual(rb.devs[1]['id'], 1) self.assertEqual(dev_id, 1) def test_set_dev_weight(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.rebalance() r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 128, 1: 128, 2: 256, 3: 256}) rb.set_dev_weight(0, 0.75) rb.set_dev_weight(1, 0.25) rb.pretend_min_part_hours_passed() rb.rebalance() r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 192, 1: 64, 2: 256, 3: 256}) def test_remove_dev(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.rebalance() r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 192, 1: 192, 2: 192, 3: 192}) rb.remove_dev(1) rb.pretend_min_part_hours_passed() rb.rebalance() r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 256, 2: 256, 3: 256}) def test_round_off_error(self): # 3 nodes with 11 disks each is particularly problematic. Probably has # to do with the binary repr. of 1/33? Those ones look suspicious... # # >>> bin(int(struct.pack('!f', 1.0/(33)).encode('hex'), 16)) # '0b111100111110000011111000010000' rb = ring.RingBuilder(8, 3, 1) for dev_id, (region, zone) in enumerate( 11 * [(0, 0), (1, 10), (1, 11)]): rb.add_dev({'id': dev_id, 'region': region, 'zone': zone, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000 + region * 100 + zone, 'device': 'sda%d' % dev_id}) rb.rebalance() self.assertEqual(self._partition_counts(rb, 'zone'), {0: 256, 10: 256, 11: 256}) wanted_by_zone = defaultdict(lambda: defaultdict(int)) for dev in rb._iter_devs(): wanted_by_zone[dev['zone']][dev['parts_wanted']] += 1 # We're nicely balanced, but parts_wanted is slightly lumpy # because reasons. self.assertEqual(wanted_by_zone, { 0: {0: 10, 1: 1}, 10: {0: 11}, 11: {0: 10, -1: 1}}) def test_remove_a_lot(self): rb = ring.RingBuilder(3, 3, 1) rb.add_dev({'id': 0, 'device': 'd0', 'ip': '10.0.0.1', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 1}) rb.add_dev({'id': 1, 'device': 'd1', 'ip': '10.0.0.2', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 2}) rb.add_dev({'id': 2, 'device': 'd2', 'ip': '10.0.0.3', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 3}) rb.add_dev({'id': 3, 'device': 'd3', 'ip': '10.0.0.1', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 1}) rb.add_dev({'id': 4, 'device': 'd4', 'ip': '10.0.0.2', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 2}) rb.add_dev({'id': 5, 'device': 'd5', 'ip': '10.0.0.3', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 3}) rb.rebalance() rb.validate() # this has to put more than 1/3 of the partitions in the # cluster on removed devices in order to ensure that at least # one partition has multiple replicas that need to move. # # (for an N-replica ring, it's more than 1/N of the # partitions, of course) rb.remove_dev(3) rb.remove_dev(4) rb.remove_dev(5) rb.rebalance() rb.validate() def test_remove_zero_weighted(self): rb = ring.RingBuilder(8, 3, 0) rb.add_dev({'id': 0, 'device': 'd0', 'ip': '10.0.0.1', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 1}) rb.add_dev({'id': 1, 'device': 'd1', 'ip': '10.0.0.2', 'port': 6202, 'weight': 0.0, 'region': 0, 'zone': 2}) rb.add_dev({'id': 2, 'device': 'd2', 'ip': '10.0.0.3', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 3}) rb.add_dev({'id': 3, 'device': 'd3', 'ip': '10.0.0.1', 'port': 6202, 'weight': 1000.0, 'region': 0, 'zone': 1}) rb.rebalance() rb.remove_dev(1) parts, balance, removed = rb.rebalance() self.assertEqual(removed, 1) def test_shuffled_gather(self): if self._shuffled_gather_helper() and \ self._shuffled_gather_helper(): raise AssertionError('It is highly likely the ring is no ' 'longer shuffling the set of partitions ' 'to reassign on a rebalance.') def _shuffled_gather_helper(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.rebalance() rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) replica_plan = rb._build_replica_plan() rb._set_parts_wanted(replica_plan) for dev in rb._iter_devs(): dev['tiers'] = utils.tiers_for_dev(dev) assign_parts = defaultdict(list) rb._gather_parts_for_balance(assign_parts, replica_plan) max_run = 0 run = 0 last_part = 0 for part, _ in assign_parts.items(): if part > last_part: run += 1 else: if run > max_run: max_run = run run = 0 last_part = part if run > max_run: max_run = run return max_run > len(assign_parts) / 2 def test_initial_balance(self): # 2 boxes, 2 drives each in zone 1 # 1 box, 2 drives in zone 2 # # This is balanceable, but there used to be some nondeterminism in # rebalance() that would sometimes give you an imbalanced ring. rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'region': 1, 'zone': 1, 'weight': 4000.0, 'ip': '10.1.1.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'region': 1, 'zone': 1, 'weight': 4000.0, 'ip': '10.1.1.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'region': 1, 'zone': 1, 'weight': 4000.0, 'ip': '10.1.1.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'region': 1, 'zone': 1, 'weight': 4000.0, 'ip': '10.1.1.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'region': 1, 'zone': 2, 'weight': 4000.0, 'ip': '10.1.1.3', 'port': 10000, 'device': 'sda'}) rb.add_dev({'region': 1, 'zone': 2, 'weight': 4000.0, 'ip': '10.1.1.3', 'port': 10000, 'device': 'sdb'}) _, balance, _ = rb.rebalance(seed=2) # maybe not *perfect*, but should be close self.assertLessEqual(balance, 1) def test_multitier_partial(self): # Multitier test, nothing full rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 2, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 3, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.rebalance() rb.validate() for part in range(rb.parts): counts = defaultdict(lambda: defaultdict(int)) for replica in range(rb.replicas): dev = rb.devs[rb._replica2part2dev[replica][part]] counts['region'][dev['region']] += 1 counts['zone'][dev['zone']] += 1 if any(c > 1 for c in counts['region'].values()): raise AssertionError( "Partition %d not evenly region-distributed (got %r)" % (part, counts['region'])) if any(c > 1 for c in counts['zone'].values()): raise AssertionError( "Partition %d not evenly zone-distributed (got %r)" % (part, counts['zone'])) # Multitier test, zones full, nodes not full rb = ring.RingBuilder(8, 6, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdf'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sdg'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sdh'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sdi'}) rb.rebalance() rb.validate() for part in range(rb.parts): counts = defaultdict(lambda: defaultdict(int)) for replica in range(rb.replicas): dev = rb.devs[rb._replica2part2dev[replica][part]] counts['zone'][dev['zone']] += 1 counts['dev_id'][dev['id']] += 1 if counts['zone'] != {0: 2, 1: 2, 2: 2}: raise AssertionError( "Partition %d not evenly distributed (got %r)" % (part, counts['zone'])) for dev_id, replica_count in counts['dev_id'].items(): if replica_count > 1: raise AssertionError( "Partition %d is on device %d more than once (%r)" % (part, dev_id, counts['dev_id'])) def test_multitier_full(self): # Multitier test, #replicas == #devs rb = ring.RingBuilder(8, 6, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdf'}) rb.rebalance() rb.validate() for part in range(rb.parts): counts = defaultdict(lambda: defaultdict(int)) for replica in range(rb.replicas): dev = rb.devs[rb._replica2part2dev[replica][part]] counts['zone'][dev['zone']] += 1 counts['dev_id'][dev['id']] += 1 if counts['zone'] != {0: 2, 1: 2, 2: 2}: raise AssertionError( "Partition %d not evenly distributed (got %r)" % (part, counts['zone'])) for dev_id, replica_count in counts['dev_id'].items(): if replica_count != 1: raise AssertionError( "Partition %d is on device %d %d times, not 1 (%r)" % (part, dev_id, replica_count, counts['dev_id'])) def test_multitier_overfull(self): # Multitier test, #replicas > #zones (to prove even distribution) rb = ring.RingBuilder(8, 8, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdg'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdd'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdh'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdf'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdi'}) rb.rebalance() rb.validate() for part in range(rb.parts): counts = defaultdict(lambda: defaultdict(int)) for replica in range(rb.replicas): dev = rb.devs[rb._replica2part2dev[replica][part]] counts['zone'][dev['zone']] += 1 counts['dev_id'][dev['id']] += 1 self.assertEqual(8, sum(counts['zone'].values())) for zone, replica_count in counts['zone'].items(): if replica_count not in (2, 3): raise AssertionError( "Partition %d not evenly distributed (got %r)" % (part, counts['zone'])) for dev_id, replica_count in counts['dev_id'].items(): if replica_count not in (1, 2): raise AssertionError( "Partition %d is on device %d %d times, " "not 1 or 2 (%r)" % (part, dev_id, replica_count, counts['dev_id'])) def test_multitier_expansion_more_devices(self): rb = ring.RingBuilder(8, 6, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 2, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.rebalance() rb.validate() rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 11, 'region': 0, 'zone': 2, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf'}) for _ in range(5): rb.pretend_min_part_hours_passed() rb.rebalance() rb.validate() for part in range(rb.parts): counts = dict(zone=defaultdict(int), dev_id=defaultdict(int)) for replica in range(rb.replicas): dev = rb.devs[rb._replica2part2dev[replica][part]] counts['zone'][dev['zone']] += 1 counts['dev_id'][dev['id']] += 1 self.assertEqual({0: 2, 1: 2, 2: 2}, dict(counts['zone'])) # each part is assigned once to six unique devices self.assertEqual((counts['dev_id'].values()), [1] * 6) self.assertEqual(len(set(counts['dev_id'].keys())), 6) def test_multitier_part_moves_with_0_min_part_hours(self): rb = ring.RingBuilder(8, 3, 0) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde1'}) rb.rebalance() rb.validate() # min_part_hours is 0, so we're clear to move 2 replicas to # new devs rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc1'}) rb.rebalance() rb.validate() for part in range(rb.parts): devs = set() for replica in range(rb.replicas): devs.add(rb._replica2part2dev[replica][part]) if len(devs) != 3: raise AssertionError( "Partition %d not on 3 devs (got %r)" % (part, devs)) def test_multitier_part_moves_with_positive_min_part_hours(self): rb = ring.RingBuilder(8, 3, 99) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde1'}) rb.rebalance() rb.validate() # min_part_hours is >0, so we'll only be able to move 1 # replica to a new home rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc1'}) rb.pretend_min_part_hours_passed() rb.rebalance() rb.validate() for part in range(rb.parts): devs = set() for replica in range(rb.replicas): devs.add(rb._replica2part2dev[replica][part]) if not any(rb.devs[dev_id]['zone'] == 1 for dev_id in devs): raise AssertionError( "Partition %d did not move (got %r)" % (part, devs)) def test_multitier_dont_move_too_many_replicas(self): rb = ring.RingBuilder(8, 3, 1) # there'll be at least one replica in z0 and z1 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.rebalance() rb.validate() # only 1 replica should move rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 4, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf1'}) rb.pretend_min_part_hours_passed() rb.rebalance() rb.validate() for part in range(rb.parts): zones = set() for replica in range(rb.replicas): zones.add(rb.devs[rb._replica2part2dev[replica][part]]['zone']) if len(zones) != 3: raise AssertionError( "Partition %d not in 3 zones (got %r)" % (part, zones)) if 0 not in zones or 1 not in zones: raise AssertionError( "Partition %d not in zones 0 and 1 (got %r)" % (part, zones)) def test_min_part_hours_zero_will_move_one_replica(self): rb = ring.RingBuilder(8, 3, 0) # there'll be at least one replica in z0 and z1 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.rebalance(seed=1) rb.validate() rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 4, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf1'}) rb.rebalance(seed=3) rb.validate() self.assertEqual(0, rb.dispersion) # Only one replica could move, so some zones are quite unbalanced self.assertAlmostEqual(rb.get_balance(), 66.66, delta=0.5) # There was only zone 0 and 1 before adding more devices. Only one # replica should have been moved, therefore we expect 256 parts in zone # 0 and 1, and a total of 256 in zone 2,3, and 4 expected = defaultdict(int, {0: 256, 1: 256, 2: 86, 3: 85, 4: 85}) self.assertEqual(expected, self._partition_counts(rb, key='zone')) zone_histogram = defaultdict(int) for part in range(rb.parts): zones = [ rb.devs[rb._replica2part2dev[replica][part]]['zone'] for replica in range(rb.replicas)] zone_histogram[tuple(sorted(zones))] += 1 # We expect that every partition moved exactly one replica expected = { (0, 1, 2): 86, (0, 1, 3): 85, (0, 1, 4): 85, } self.assertEqual(zone_histogram, expected) # After rebalancing one more times, we expect that everything is in a # good state rb.rebalance(seed=3) self.assertEqual(0, rb.dispersion) # a balance of w/i a 1% isn't too bad for 3 replicas on 7 # devices when part power is only 8 self.assertAlmostEqual(rb.get_balance(), 0, delta=0.5) # every zone has either 153 or 154 parts for zone, count in self._partition_counts( rb, key='zone').items(): self.assertAlmostEqual(153.5, count, delta=1) parts_with_moved_count = defaultdict(int) for part in range(rb.parts): zones = set() for replica in range(rb.replicas): zones.add(rb.devs[rb._replica2part2dev[replica][part]]['zone']) moved_replicas = len(zones - {0, 1}) parts_with_moved_count[moved_replicas] += 1 # as usual, the real numbers depend on the seed, but we want to # validate a few things here: # # 1) every part had to move one replica to hit dispersion (so no # one can have a moved count 0) # # 2) it's quite reasonable that some small percent of parts will # have a replica in {0, 1, X} (meaning only one replica of the # part moved) # # 3) when min_part_hours is 0, more than one replica of a part # can move in a rebalance, and since that movement would get to # better dispersion faster we expect to observe most parts in # {[0,1], X, X} (meaning *two* replicas of the part moved) # # 4) there's plenty of weight in z0 & z1 to hold a whole # replicanth, so there is no reason for any part to have to move # all three replicas out of those zones (meaning no one can have # a moved count 3) # expected = { 1: 52, 2: 204, } self.assertEqual(parts_with_moved_count, expected) def test_rerebalance(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.rebalance() counts = self._partition_counts(rb) self.assertEqual(counts, {0: 256, 1: 256, 2: 256}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.pretend_min_part_hours_passed() rb.rebalance() counts = self._partition_counts(rb) self.assertEqual(counts, {0: 192, 1: 192, 2: 192, 3: 192}) rb.set_dev_weight(3, 100) rb.rebalance() counts = self._partition_counts(rb) self.assertEqual(counts[3], 256) def test_add_rebalance_add_rebalance_delete_rebalance(self): # Test for https://bugs.launchpad.net/swift/+bug/845952 # min_part of 0 to allow for rapid rebalancing rb = ring.RingBuilder(8, 3, 0) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.rebalance() rb.validate() rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10005, 'device': 'sda1'}) rb.rebalance() rb.validate() rb.remove_dev(1) # well now we have only one device in z0 rb.set_overload(0.5) rb.rebalance() rb.validate() def test_remove_last_partition_from_zero_weight(self): rb = ring.RingBuilder(4, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 1, 'weight': 1.0, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 2, 'weight': 1.0, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 1.0, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 3, 'weight': 1.0, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 3, 'weight': 1.0, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 3, 'weight': 1.0, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 0.4, 'ip': '127.0.0.3', 'port': 10001, 'device': 'zero'}) zero_weight_dev = 3 rb.rebalance(seed=1) # We want at least one partition with replicas only in zone 2 and 3 # due to device weights. It would *like* to spread out into zone 1, # but can't, due to device weight. # # Also, we want such a partition to have a replica on device 3, # which we will then reduce to zero weight. This should cause the # removal of the replica from device 3. # # Getting this to happen by chance is hard, so let's just set up a # builder so that it's in the state we want. This is a synthetic # example; while the bug has happened on a real cluster, that # builder file had a part_power of 16, so its contents are much too # big to include here. rb._replica2part2dev = [ # these are the relevant ones # | | | # v v v array('H', [2, 5, 6, 2, 5, 6, 2, 5, 6, 2, 5, 6, 2, 5, 6, 2]), array('H', [1, 4, 1, 4, 1, 4, 1, 4, 1, 4, 1, 4, 1, 4, 1, 4]), array('H', [0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 5, 6, 2, 5, 6])] # fix up bookkeeping new_dev_parts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: new_dev_parts[dev_id] += 1 for dev in rb._iter_devs(): dev['parts'] = new_dev_parts[dev['id']] rb.set_dev_weight(zero_weight_dev, 0.0) rb.pretend_min_part_hours_passed() rb.rebalance(seed=1) node_counts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: node_counts[dev_id] += 1 self.assertEqual(node_counts[zero_weight_dev], 0) # it's as balanced as it gets, so nothing moves anymore rb.pretend_min_part_hours_passed() parts_moved, _balance, _removed = rb.rebalance(seed=1) new_node_counts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: new_node_counts[dev_id] += 1 del node_counts[zero_weight_dev] self.assertEqual(node_counts, new_node_counts) self.assertEqual(parts_moved, 0) def test_part_swapping_problem(self): rb = ring.RingBuilder(4, 3, 1) # 127.0.0.1 (2 devs) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) # 127.0.0.2 (3 devs) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdc'}) expected = { '127.0.0.1': 1.2, '127.0.0.2': 1.7999999999999998, } for wr in (rb._build_weighted_replicas_by_tier(), rb._build_wanted_replicas_by_tier(), rb._build_target_replicas_by_tier()): self.assertEqual(expected, {t[-1]: r for (t, r) in wr.items() if len(t) == 3}) self.assertEqual(rb.get_required_overload(), 0) rb.rebalance(seed=3) # so 127.0.0.1 ended up with... tier = (0, 0, '127.0.0.1') # ... 6 parts with 1 replicas self.assertEqual(rb._dispersion_graph[tier][1], 12) # ... 4 parts with 2 replicas self.assertEqual(rb._dispersion_graph[tier][2], 4) # but since we only have two tiers, this is *totally* dispersed self.assertEqual(0, rb.dispersion) # small rings are hard to balance... expected = {0: 10, 1: 10, 2: 10, 3: 9, 4: 9} self.assertEqual(expected, {d['id']: d['parts'] for d in rb._iter_devs()}) # everyone wants 9.6 parts expected = { 0: 4.166666666666671, 1: 4.166666666666671, 2: 4.166666666666671, 3: -6.25, 4: -6.25, } self.assertEqual(expected, rb._build_balance_per_dev()) # original sorted _replica2part2dev """ rb._replica2part2dev = [ array('H', [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1]), array('H', [1, 1, 1, 1, 2, 2, 2, 3, 3, 3, 2, 2, 2, 3, 3, 3]), array('H', [2, 2, 2, 2, 3, 3, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4])] """ # now imagine if we came along this _replica2part2dev through no # fault of our own; if instead of the 12 parts with only one # replica on 127.0.0.1 being split evenly (6 and 6) on device's # 0 and 1 - device 1 inexplicitly had 3 extra parts rb._replica2part2dev = [ # these are the relevant one's here # | | | # v v v array('H', [0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1]), array('H', [1, 1, 1, 1, 2, 2, 2, 3, 3, 3, 2, 2, 2, 3, 3, 3]), array('H', [2, 2, 2, 2, 3, 3, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4])] # fix up bookkeeping new_dev_parts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: new_dev_parts[dev_id] += 1 for dev in rb._iter_devs(): dev['parts'] = new_dev_parts[dev['id']] rb.pretend_min_part_hours_passed() rb.rebalance() expected = { 0: 4.166666666666671, 1: 4.166666666666671, 2: 4.166666666666671, 3: -6.25, 4: -6.25, } self.assertEqual(expected, rb._build_balance_per_dev()) self.assertEqual(rb.get_balance(), 6.25) def test_wrong_tier_with_no_where_to_go(self): rb = ring.RingBuilder(4, 3, 1) # 127.0.0.1 (even devices) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 900, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 900, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 900, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) # 127.0.0.2 (odd devices) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdd'}) expected = { '127.0.0.1': 1.75, '127.0.0.2': 1.25, } for wr in (rb._build_weighted_replicas_by_tier(), rb._build_wanted_replicas_by_tier(), rb._build_target_replicas_by_tier()): self.assertEqual(expected, {t[-1]: r for (t, r) in wr.items() if len(t) == 3}) self.assertEqual(rb.get_required_overload(), 0) rb.rebalance(seed=3) # so 127.0.0.1 ended up with... tier = (0, 0, '127.0.0.1') # ... 4 parts with 1 replicas self.assertEqual(rb._dispersion_graph[tier][1], 4) # ... 12 parts with 2 replicas self.assertEqual(rb._dispersion_graph[tier][2], 12) # ... and of course 0 parts with 3 replicas self.assertEqual(rb._dispersion_graph[tier][3], 0) # but since we only have two tiers, this is *totally* dispersed self.assertEqual(0, rb.dispersion) # small rings are hard to balance, but it's possible when # part-replicas (3 * 2 ** 4) can go evenly into device weights # (4800) like we've done here expected = { 0: 1, 2: 9, 4: 9, 6: 9, 1: 5, 3: 5, 5: 5, 7: 5, } self.assertEqual(expected, {d['id']: d['parts'] for d in rb._iter_devs()}) expected = { 0: 0.0, 1: 0.0, 2: 0.0, 3: 0.0, 4: 0.0, 5: 0.0, 6: 0.0, 7: 0.0, } self.assertEqual(expected, rb._build_balance_per_dev()) # all devices have exactly the # of parts they want expected = { 0: 0, 2: 0, 4: 0, 6: 0, 1: 0, 3: 0, 5: 0, 7: 0, } self.assertEqual(expected, {d['id']: d['parts_wanted'] for d in rb._iter_devs()}) # original sorted _replica2part2dev """ rb._replica2part2dev = [ array('H', [0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, ]), array('H', [4, 4, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 1, 1, 1, 1, ]), array('H', [1, 3, 3, 3, 3, 3, 5, 5, 5, 5, 5, 7, 7, 7, 7, 7, ])] """ # now imagine if we came along this _replica2part2dev through no # fault of our own; and device 0 had extra parts, but both # copies of the other replicas were already in the other tier! rb._replica2part2dev = [ # these are the relevant one's here # | | # v v array('H', [2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 0, 0]), array('H', [4, 4, 4, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 1, 1, 1]), array('H', [1, 1, 3, 3, 3, 3, 5, 5, 5, 5, 5, 7, 7, 7, 7, 7])] # fix up bookkeeping new_dev_parts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: new_dev_parts[dev_id] += 1 for dev in rb._iter_devs(): dev['parts'] = new_dev_parts[dev['id']] replica_plan = rb._build_replica_plan() rb._set_parts_wanted(replica_plan) expected = { 0: -1, # this device wants to shed 2: 0, 4: 0, 6: 0, 1: 0, 3: 1, # there's devices with room on the other server 5: 0, 7: 0, } self.assertEqual(expected, {d['id']: d['parts_wanted'] for d in rb._iter_devs()}) rb.pretend_min_part_hours_passed() rb.rebalance() self.assertEqual(rb.get_balance(), 0) def test_multiple_duplicate_device_assignment(self): rb = ring.RingBuilder(4, 4, 1) devs = [ 'r1z1-127.0.0.1:6200/d1', 'r1z1-127.0.0.1:6201/d2', 'r1z1-127.0.0.1:6202/d3', 'r1z1-127.0.0.1:33443/d4', 'r1z1-127.0.0.2:6200/d5', 'r1z1-127.0.0.2:6201/d6', 'r1z1-127.0.0.2:6202/d7', 'r1z1-127.0.0.2:6202/d8', ] for add_value in devs: dev = utils.parse_add_value(add_value) dev['weight'] = 1.0 rb.add_dev(dev) rb.rebalance() rb._replica2part2dev = [ # these are the relevant one's here # | | | | | # v v v v v array('H', [0, 1, 2, 3, 3, 0, 0, 0, 4, 6, 4, 4, 4, 4, 4, 4]), array('H', [0, 1, 3, 1, 1, 1, 1, 1, 5, 7, 5, 5, 5, 5, 5, 5]), array('H', [0, 1, 2, 2, 2, 2, 2, 2, 4, 6, 6, 6, 6, 6, 6, 6]), array('H', [0, 3, 2, 3, 3, 3, 3, 3, 5, 7, 7, 7, 7, 7, 7, 7]) # ^ # | # this sort of thing worked already ] # fix up bookkeeping new_dev_parts = defaultdict(int) for part2dev_id in rb._replica2part2dev: for dev_id in part2dev_id: new_dev_parts[dev_id] += 1 for dev in rb._iter_devs(): dev['parts'] = new_dev_parts[dev['id']] rb.pretend_min_part_hours_passed() rb.rebalance() rb.validate() def test_region_fullness_with_balanceable_ring(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 1, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 2, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10005, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 2, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10006, 'device': 'sda1'}) rb.add_dev({'id': 6, 'region': 3, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10007, 'device': 'sda1'}) rb.add_dev({'id': 7, 'region': 3, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10008, 'device': 'sda1'}) rb.rebalance(seed=2) population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 192, 1: 192, 2: 192, 3: 192}) def test_region_fullness_with_unbalanceable_ring(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 2, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 1, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 1, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.rebalance(seed=2) population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 512, 1: 256}) def test_adding_region_slowly_with_unbalanceable_ring(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc1'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb1'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdc1'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 1, 'weight': 0.5, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdd1'}) rb.rebalance(seed=2) rb.add_dev({'id': 2, 'region': 1, 'zone': 0, 'weight': 0.25, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 1, 'zone': 1, 'weight': 0.25, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.pretend_min_part_hours_passed() changed_parts, _balance, _removed = rb.rebalance(seed=2) # there's not enough room in r1 for every partition to have a replica # in it, so only 86 assignments occur in r1 (that's ~1/5 of the total, # since r1 has 1/5 of the weight). population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 682, 1: 86}) # really 86 parts *should* move (to the new region) but to avoid # accidentally picking up too many and causing some parts to randomly # flop around devices in the original region - our gather algorithm # is conservative when picking up only from devices that are for sure # holding more parts than they want (math.ceil() of the replica_plan) # which guarantees any parts picked up will have new homes in a better # tier or failure_domain. self.assertEqual(86, changed_parts) # and since there's not enough room, subsequent rebalances will not # cause additional assignments to r1 rb.pretend_min_part_hours_passed() rb.rebalance(seed=2) rb.validate() population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 682, 1: 86}) # after you add more weight, more partition assignments move rb.set_dev_weight(2, 0.5) rb.set_dev_weight(3, 0.5) rb.pretend_min_part_hours_passed() rb.rebalance(seed=2) rb.validate() population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 614, 1: 154}) rb.set_dev_weight(2, 1.0) rb.set_dev_weight(3, 1.0) rb.pretend_min_part_hours_passed() rb.rebalance(seed=2) rb.validate() population_by_region = self._get_population_by_region(rb) self.assertEqual(population_by_region, {0: 512, 1: 256}) def test_avoid_tier_change_new_region(self): rb = ring.RingBuilder(8, 3, 1) for i in range(5): rb.add_dev({'id': i, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.1', 'port': i, 'device': 'sda1'}) rb.rebalance(seed=2) # Add a new device in new region to a balanced ring rb.add_dev({'id': 5, 'region': 1, 'zone': 0, 'weight': 0, 'ip': '127.0.0.5', 'port': 10000, 'device': 'sda1'}) # Increase the weight of region 1 slowly moved_partitions = [] errors = [] for weight in range(0, 101, 10): rb.set_dev_weight(5, weight) rb.pretend_min_part_hours_passed() changed_parts, _balance, _removed = rb.rebalance(seed=2) rb.validate() moved_partitions.append(changed_parts) # Ensure that the second region has enough partitions # Otherwise there will be replicas at risk min_parts_for_r1 = ceil(weight / (500.0 + weight) * 768) parts_for_r1 = self._get_population_by_region(rb).get(1, 0) try: self.assertEqual(min_parts_for_r1, parts_for_r1) except AssertionError: errors.append('weight %s got %s parts but expected %s' % ( weight, parts_for_r1, min_parts_for_r1)) self.assertFalse(errors) # Number of partitions moved on each rebalance # 10/510 * 768 ~ 15.06 -> move at least 15 partitions in first step ref = [0, 16, 14, 14, 13, 13, 13, 12, 11, 12, 10] self.assertEqual(ref, moved_partitions) def test_set_replicas_increase(self): rb = ring.RingBuilder(8, 2, 0) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.rebalance() rb.validate() rb.replicas = 2.1 rb.rebalance() rb.validate() self.assertEqual([len(p2d) for p2d in rb._replica2part2dev], [256, 256, 25]) rb.replicas = 2.2 rb.rebalance() rb.validate() self.assertEqual([len(p2d) for p2d in rb._replica2part2dev], [256, 256, 51]) def test_set_replicas_decrease(self): rb = ring.RingBuilder(4, 5, 0) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.rebalance() rb.validate() rb.replicas = 4.9 rb.rebalance() rb.validate() self.assertEqual([len(p2d) for p2d in rb._replica2part2dev], [16, 16, 16, 16, 14]) # cross a couple of integer thresholds (4 and 3) rb.replicas = 2.5 rb.rebalance() rb.validate() self.assertEqual([len(p2d) for p2d in rb._replica2part2dev], [16, 16, 8]) def test_fractional_replicas_rebalance(self): rb = ring.RingBuilder(8, 2.5, 0) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.rebalance() # passes by not crashing rb.validate() # also passes by not crashing self.assertEqual([len(p2d) for p2d in rb._replica2part2dev], [256, 256, 128]) def test_create_add_dev_add_replica_rebalance(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.set_replicas(4) rb.rebalance() # this would crash since parts_wanted was not set rb.validate() def test_reduce_replicas_after_remove_device(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.rebalance() rb.remove_dev(0) self.assertRaises(exceptions.RingValidationError, rb.rebalance) rb.set_replicas(2) rb.rebalance() rb.validate() def test_rebalance_post_upgrade(self): rb = ring.RingBuilder(8, 3, 1) # 5 devices: 5 is the smallest number that does not divide 3 * 2^8, # which forces some rounding to happen. rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde'}) rb.rebalance() rb.validate() # Older versions of the ring builder code would round down when # computing parts_wanted, while the new code rounds up. Make sure we # can handle a ring built by the old method. # # This code mimics the old _set_parts_wanted. weight_of_one_part = rb.weight_of_one_part() for dev in rb._iter_devs(): if not dev['weight']: dev['parts_wanted'] = -rb.parts * rb.replicas else: dev['parts_wanted'] = ( int(weight_of_one_part * dev['weight']) - dev['parts']) rb.pretend_min_part_hours_passed() rb.rebalance() # this crashes unless rebalance resets parts_wanted rb.validate() def test_add_replicas_then_rebalance_respects_weight(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdg'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdh'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 2, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdi'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 2, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdj'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdk'}) rb.add_dev({'id': 11, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdl'}) rb.rebalance(seed=1) r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 96, 1: 96, 2: 32, 3: 32, 4: 96, 5: 96, 6: 32, 7: 32, 8: 96, 9: 96, 10: 32, 11: 32}) rb.replicas *= 2 rb.rebalance(seed=1) r = rb.get_ring() counts = {} for part2dev_id in r._replica2part2dev_id: for dev_id in part2dev_id: counts[dev_id] = counts.get(dev_id, 0) + 1 self.assertEqual(counts, {0: 192, 1: 192, 2: 64, 3: 64, 4: 192, 5: 192, 6: 64, 7: 64, 8: 192, 9: 192, 10: 64, 11: 64}) def test_overload(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdf'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdg'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdh'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdi'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdc'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdj'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdk'}) rb.add_dev({'id': 11, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdl'}) rb.rebalance(seed=12345) rb.validate() # sanity check: balance respects weights, so default part_counts = self._partition_counts(rb, key='zone') self.assertEqual(part_counts[0], 192) self.assertEqual(part_counts[1], 192) self.assertEqual(part_counts[2], 384) # Devices 0 and 1 take 10% more than their fair shares by weight since # overload is 10% (0.1). rb.set_overload(0.1) rb.pretend_min_part_hours_passed() rb.rebalance() part_counts = self._partition_counts(rb, key='zone') self.assertEqual(part_counts[0], 212) self.assertEqual(part_counts[1], 211) self.assertEqual(part_counts[2], 345) # Now, devices 0 and 1 take 50% more than their fair shares by # weight. rb.set_overload(0.5) for _ in range(3): rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) part_counts = self._partition_counts(rb, key='zone') self.assertEqual(part_counts[0], 256) self.assertEqual(part_counts[1], 256) self.assertEqual(part_counts[2], 256) # Devices 0 and 1 may take up to 75% over their fair share, but the # placement algorithm only wants to spread things out evenly between # all drives, so the devices stay at 50% more. rb.set_overload(0.75) for _ in range(3): rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) part_counts = self._partition_counts(rb, key='zone') self.assertEqual(part_counts[0], 256) self.assertEqual(part_counts[1], 256) self.assertEqual(part_counts[2], 256) def test_unoverload(self): # Start off needing overload to balance, then add capacity until we # don't need overload any more and see that things still balance. # Overload doesn't prevent optimal balancing. rb = ring.RingBuilder(8, 3, 1) rb.set_overload(0.125) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 11, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdc'}) rb.rebalance(seed=12345) # sanity check: our overload is big enough to balance things part_counts = self._partition_counts(rb, key='ip') self.assertEqual(part_counts['127.0.0.1'], 216) self.assertEqual(part_counts['127.0.0.2'], 216) self.assertEqual(part_counts['127.0.0.3'], 336) # Add some weight: balance improves for dev in rb.devs: if dev['ip'] in ('127.0.0.1', '127.0.0.2'): rb.set_dev_weight(dev['id'], 1.22) rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) part_counts = self._partition_counts(rb, key='ip') self.assertEqual(part_counts['127.0.0.1'], 238) self.assertEqual(part_counts['127.0.0.2'], 237) self.assertEqual(part_counts['127.0.0.3'], 293) # Even out the weights: balance becomes perfect for dev in rb.devs: if dev['ip'] in ('127.0.0.1', '127.0.0.2'): rb.set_dev_weight(dev['id'], 2) rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) part_counts = self._partition_counts(rb, key='ip') self.assertEqual(part_counts['127.0.0.1'], 256) self.assertEqual(part_counts['127.0.0.2'], 256) self.assertEqual(part_counts['127.0.0.3'], 256) # Add a new server: balance stays optimal rb.add_dev({'id': 12, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.4', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 13, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.4', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 14, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.4', 'port': 10000, 'device': 'sdf'}) rb.add_dev({'id': 15, 'region': 0, 'zone': 0, 'weight': 2, 'ip': '127.0.0.4', 'port': 10000, 'device': 'sdf'}) # we're moving more than 1/3 of the replicas but fewer than 2/3, so # we have to do this twice rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) rb.pretend_min_part_hours_passed() rb.rebalance(seed=12345) expected = { '127.0.0.1': 192, '127.0.0.2': 192, '127.0.0.3': 192, '127.0.0.4': 192, } part_counts = self._partition_counts(rb, key='ip') self.assertEqual(part_counts, expected) def test_overload_keeps_balanceable_things_balanced_initially(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 8, 'ip': '10.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 8, 'ip': '10.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.3', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.3', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.4', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.4', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.5', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.5', 'port': 10000, 'device': 'sdb'}) rb.set_overload(99999) rb.rebalance(seed=12345) part_counts = self._partition_counts(rb) self.assertEqual(part_counts, { 0: 128, 1: 128, 2: 64, 3: 64, 4: 64, 5: 64, 6: 64, 7: 64, 8: 64, 9: 64, }) def test_overload_keeps_balanceable_things_balanced_on_rebalance(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 8, 'ip': '10.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 8, 'ip': '10.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.3', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.3', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.4', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.4', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.5', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '10.0.0.5', 'port': 10000, 'device': 'sdb'}) rb.set_overload(99999) rb.rebalance(seed=123) part_counts = self._partition_counts(rb) self.assertEqual(part_counts, { 0: 128, 1: 128, 2: 64, 3: 64, 4: 64, 5: 64, 6: 64, 7: 64, 8: 64, 9: 64, }) # swap weights between 10.0.0.1 and 10.0.0.2 rb.set_dev_weight(0, 4) rb.set_dev_weight(1, 4) rb.set_dev_weight(2, 8) rb.set_dev_weight(1, 8) rb.rebalance(seed=456) part_counts = self._partition_counts(rb) self.assertEqual(part_counts, { 0: 128, 1: 128, 2: 64, 3: 64, 4: 64, 5: 64, 6: 64, 7: 64, 8: 64, 9: 64, }) def test_server_per_port(self): # 3 servers, 3 disks each, with each disk on its own port rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.1', 'port': 10000, 'device': 'sdx'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.1', 'port': 10001, 'device': 'sdy'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.2', 'port': 10000, 'device': 'sdx'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.2', 'port': 10001, 'device': 'sdy'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.3', 'port': 10000, 'device': 'sdx'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.3', 'port': 10001, 'device': 'sdy'}) rb.rebalance(seed=1) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.1', 'port': 10002, 'device': 'sdz'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.2', 'port': 10002, 'device': 'sdz'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '10.0.0.3', 'port': 10002, 'device': 'sdz'}) rb.pretend_min_part_hours_passed() rb.rebalance(seed=1) poorly_dispersed = [] for part in range(rb.parts): on_nodes = set() for replica in range(rb.replicas): dev_id = rb._replica2part2dev[replica][part] on_nodes.add(rb.devs[dev_id]['ip']) if len(on_nodes) < rb.replicas: poorly_dispersed.append(part) self.assertEqual(poorly_dispersed, []) def test_load(self): rb = ring.RingBuilder(8, 3, 1) devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda1', 'meta': 'meta0'}, {'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb1', 'meta': 'meta1'}, {'id': 2, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdc1', 'meta': 'meta2'}, {'id': 3, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.3', 'port': 10003, 'device': 'sdd1'}] for d in devs: rb.add_dev(d) rb.rebalance() real_pickle = pickle.load fake_open = mock.mock_open() io_error_not_found = IOError() io_error_not_found.errno = errno.ENOENT io_error_no_perm = IOError() io_error_no_perm.errno = errno.EPERM io_error_generic = IOError() io_error_generic.errno = errno.EOPNOTSUPP try: # test a legit builder fake_pickle = mock.Mock(return_value=rb) pickle.load = fake_pickle builder = ring.RingBuilder.load('fake.builder', open=fake_open) self.assertEqual(fake_pickle.call_count, 1) fake_open.assert_has_calls([mock.call('fake.builder', 'rb')]) self.assertEqual(builder, rb) fake_pickle.reset_mock() # test old style builder fake_pickle.return_value = rb.to_dict() pickle.load = fake_pickle builder = ring.RingBuilder.load('fake.builder', open=fake_open) fake_open.assert_has_calls([mock.call('fake.builder', 'rb')]) self.assertEqual(builder.devs, rb.devs) fake_pickle.reset_mock() # test old devs but no meta no_meta_builder = rb for dev in no_meta_builder.devs: del(dev['meta']) fake_pickle.return_value = no_meta_builder pickle.load = fake_pickle builder = ring.RingBuilder.load('fake.builder', open=fake_open) fake_open.assert_has_calls([mock.call('fake.builder', 'rb')]) self.assertEqual(builder.devs, rb.devs) # test an empty builder fake_pickle.side_effect = EOFError pickle.load = fake_pickle self.assertRaises(exceptions.UnPicklingError, ring.RingBuilder.load, 'fake.builder', open=fake_open) # test a corrupted builder fake_pickle.side_effect = pickle.UnpicklingError pickle.load = fake_pickle self.assertRaises(exceptions.UnPicklingError, ring.RingBuilder.load, 'fake.builder', open=fake_open) # test some error fake_pickle.side_effect = AttributeError pickle.load = fake_pickle self.assertRaises(exceptions.UnPicklingError, ring.RingBuilder.load, 'fake.builder', open=fake_open) finally: pickle.load = real_pickle # test non existent builder file fake_open.side_effect = io_error_not_found self.assertRaises(exceptions.FileNotFoundError, ring.RingBuilder.load, 'fake.builder', open=fake_open) # test non accessible builder file fake_open.side_effect = io_error_no_perm self.assertRaises(exceptions.PermissionError, ring.RingBuilder.load, 'fake.builder', open=fake_open) # test an error other then ENOENT and ENOPERM fake_open.side_effect = io_error_generic self.assertRaises(IOError, ring.RingBuilder.load, 'fake.builder', open=fake_open) def test_save_load(self): rb = ring.RingBuilder(8, 3, 1) devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.0', 'port': 10000, 'replication_ip': '127.0.0.0', 'replication_port': 10000, 'device': 'sda1', 'meta': 'meta0'}, {'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'replication_ip': '127.0.0.1', 'replication_port': 10001, 'device': 'sdb1', 'meta': 'meta1'}, {'id': 2, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'replication_ip': '127.0.0.2', 'replication_port': 10002, 'device': 'sdc1', 'meta': 'meta2'}, {'id': 3, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.3', 'port': 10003, 'replication_ip': '127.0.0.3', 'replication_port': 10003, 'device': 'sdd1', 'meta': ''}] rb.set_overload(3.14159) for d in devs: rb.add_dev(d) rb.rebalance() builder_file = os.path.join(self.testdir, 'test_save.builder') rb.save(builder_file) loaded_rb = ring.RingBuilder.load(builder_file) self.maxDiff = None self.assertEqual(loaded_rb.to_dict(), rb.to_dict()) self.assertEqual(loaded_rb.overload, 3.14159) @mock.patch('six.moves.builtins.open', autospec=True) @mock.patch('swift.common.ring.builder.pickle.dump', autospec=True) def test_save(self, mock_pickle_dump, mock_open): mock_open.return_value = mock_fh = mock.MagicMock() rb = ring.RingBuilder(8, 3, 1) devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda1', 'meta': 'meta0'}, {'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb1', 'meta': 'meta1'}, {'id': 2, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdc1', 'meta': 'meta2'}, {'id': 3, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.3', 'port': 10003, 'device': 'sdd1'}] for d in devs: rb.add_dev(d) rb.rebalance() rb.save('some.builder') mock_open.assert_called_once_with('some.builder', 'wb') mock_pickle_dump.assert_called_once_with(rb.to_dict(), mock_fh.__enter__(), protocol=2) def test_search_devs(self): rb = ring.RingBuilder(8, 3, 1) devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda1', 'meta': 'meta0'}, {'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb1', 'meta': 'meta1'}, {'id': 2, 'region': 1, 'zone': 2, 'weight': 2, 'ip': '127.0.0.2', 'port': 10002, 'device': 'sdc1', 'meta': 'meta2'}, {'id': 3, 'region': 1, 'zone': 3, 'weight': 2, 'ip': '127.0.0.3', 'port': 10003, 'device': 'sdd1', 'meta': 'meta3'}, {'id': 4, 'region': 2, 'zone': 4, 'weight': 1, 'ip': '127.0.0.4', 'port': 10004, 'device': 'sde1', 'meta': 'meta4', 'replication_ip': '127.0.0.10', 'replication_port': 20000}, {'id': 5, 'region': 2, 'zone': 5, 'weight': 2, 'ip': '127.0.0.5', 'port': 10005, 'device': 'sdf1', 'meta': 'meta5', 'replication_ip': '127.0.0.11', 'replication_port': 20001}, {'id': 6, 'region': 2, 'zone': 6, 'weight': 2, 'ip': '127.0.0.6', 'port': 10006, 'device': 'sdg1', 'meta': 'meta6', 'replication_ip': '127.0.0.12', 'replication_port': 20002}] for d in devs: rb.add_dev(d) rb.rebalance() res = rb.search_devs({'region': 0}) self.assertEqual(res, [devs[0], devs[1]]) res = rb.search_devs({'region': 1}) self.assertEqual(res, [devs[2], devs[3]]) res = rb.search_devs({'region': 1, 'zone': 2}) self.assertEqual(res, [devs[2]]) res = rb.search_devs({'id': 1}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'zone': 1}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'ip': '127.0.0.1'}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'ip': '127.0.0.1', 'port': 10001}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'port': 10001}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'replication_ip': '127.0.0.10'}) self.assertEqual(res, [devs[4]]) res = rb.search_devs({'replication_ip': '127.0.0.10', 'replication_port': 20000}) self.assertEqual(res, [devs[4]]) res = rb.search_devs({'replication_port': 20000}) self.assertEqual(res, [devs[4]]) res = rb.search_devs({'device': 'sdb1'}) self.assertEqual(res, [devs[1]]) res = rb.search_devs({'meta': 'meta1'}) self.assertEqual(res, [devs[1]]) def test_validate(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 11, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 12, 'region': 0, 'zone': 2, 'weight': 2, 'ip': '127.0.0.1', 'port': 10002, 'device': 'sda1'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 13, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 14, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) rb.add_dev({'id': 15, 'region': 0, 'zone': 3, 'weight': 2, 'ip': '127.0.0.1', 'port': 10003, 'device': 'sda1'}) # Degenerate case: devices added but not rebalanced yet self.assertRaises(exceptions.RingValidationError, rb.validate) rb.rebalance() counts = self._partition_counts(rb, key='zone') self.assertEqual(counts, {0: 128, 1: 128, 2: 256, 3: 256}) dev_usage, worst = rb.validate() self.assertIsNone(dev_usage) self.assertIsNone(worst) dev_usage, worst = rb.validate(stats=True) self.assertEqual(list(dev_usage), [32, 32, 64, 64, 32, 32, 32, # added zone0 32, 32, 32, # added zone1 64, 64, 64, # added zone2 64, 64, 64, # added zone3 ]) self.assertEqual(int(worst), 0) # min part hours should pin all the parts assigned to this zero # weight device onto it such that the balance will look horrible rb.set_dev_weight(2, 0) rb.rebalance() self.assertEqual(rb.validate(stats=True)[1], MAX_BALANCE) # Test not all partitions doubly accounted for rb.devs[1]['parts'] -= 1 self.assertRaises(exceptions.RingValidationError, rb.validate) rb.devs[1]['parts'] += 1 # Test non-numeric port rb.devs[1]['port'] = '10001' self.assertRaises(exceptions.RingValidationError, rb.validate) rb.devs[1]['port'] = 10001 # Test partition on nonexistent device rb.pretend_min_part_hours_passed() orig_dev_id = rb._replica2part2dev[0][0] rb._replica2part2dev[0][0] = len(rb.devs) self.assertRaises(exceptions.RingValidationError, rb.validate) rb._replica2part2dev[0][0] = orig_dev_id # Tests that validate can handle 'holes' in .devs rb.remove_dev(2) rb.pretend_min_part_hours_passed() rb.rebalance() rb.validate(stats=True) # Test partition assigned to a hole if rb.devs[2]: rb.remove_dev(2) rb.pretend_min_part_hours_passed() orig_dev_id = rb._replica2part2dev[0][0] rb._replica2part2dev[0][0] = 2 self.assertRaises(exceptions.RingValidationError, rb.validate) rb._replica2part2dev[0][0] = orig_dev_id # Validate that zero weight devices with no partitions don't count on # the 'worst' value. self.assertNotEqual(rb.validate(stats=True)[1], MAX_BALANCE) rb.add_dev({'id': 16, 'region': 0, 'zone': 0, 'weight': 0, 'ip': '127.0.0.1', 'port': 10004, 'device': 'sda1'}) rb.pretend_min_part_hours_passed() rb.rebalance() self.assertNotEqual(rb.validate(stats=True)[1], MAX_BALANCE) def test_validate_partial_replica(self): rb = ring.RingBuilder(8, 2.5, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdc'}) rb.rebalance() rb.validate() # sanity self.assertEqual(len(rb._replica2part2dev[0]), 256) self.assertEqual(len(rb._replica2part2dev[1]), 256) self.assertEqual(len(rb._replica2part2dev[2]), 128) # now swap partial replica part maps rb._replica2part2dev[1], rb._replica2part2dev[2] = \ rb._replica2part2dev[2], rb._replica2part2dev[1] self.assertRaises(exceptions.RingValidationError, rb.validate) def test_validate_duplicate_part_assignment(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sdc'}) rb.rebalance() rb.validate() # sanity # now double up a device assignment rb._replica2part2dev[1][200] = rb._replica2part2dev[2][200] with self.assertRaises(exceptions.RingValidationError) as e: rb.validate() expected = 'The partition 200 has been assigned to duplicate devices' self.assertIn(expected, str(e.exception)) def test_get_part_devices(self): rb = ring.RingBuilder(8, 3, 1) self.assertEqual(rb.get_part_devices(0), []) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.rebalance() part_devs = sorted(rb.get_part_devices(0), key=operator.itemgetter('id')) self.assertEqual(part_devs, [rb.devs[0], rb.devs[1], rb.devs[2]]) def test_get_part_devices_partial_replicas(self): rb = ring.RingBuilder(8, 2.5, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda1'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 1, 'ip': '127.0.0.1', 'port': 10001, 'device': 'sda1'}) rb.rebalance(seed=4) # note: partition 255 will only have 2 replicas part_devs = sorted(rb.get_part_devices(255), key=operator.itemgetter('id')) self.assertEqual(part_devs, [rb.devs[1], rb.devs[2]]) def test_dispersion_with_zero_weight_devices(self): rb = ring.RingBuilder(8, 3.0, 0) # add two devices to a single server in a single zone rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) # and a zero weight device rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 0, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.rebalance() self.assertEqual(rb.dispersion, 0.0) self.assertEqual(rb._dispersion_graph, { (0,): [0, 0, 0, 256], (0, 0): [0, 0, 0, 256], (0, 0, '127.0.0.1'): [0, 0, 0, 256], (0, 0, '127.0.0.1', 0): [0, 256, 0, 0], (0, 0, '127.0.0.1', 1): [0, 256, 0, 0], (0, 0, '127.0.0.1', 2): [0, 256, 0, 0], }) def test_dispersion_with_zero_weight_devices_with_parts(self): rb = ring.RingBuilder(8, 3.0, 1) # add four devices to a single server in a single zone rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.rebalance(seed=1) self.assertEqual(rb.dispersion, 0.0) self.assertEqual(rb._dispersion_graph, { (0,): [0, 0, 0, 256], (0, 0): [0, 0, 0, 256], (0, 0, '127.0.0.1'): [0, 0, 0, 256], (0, 0, '127.0.0.1', 0): [64, 192, 0, 0], (0, 0, '127.0.0.1', 1): [64, 192, 0, 0], (0, 0, '127.0.0.1', 2): [64, 192, 0, 0], (0, 0, '127.0.0.1', 3): [64, 192, 0, 0], }) # now mark a device 2 for decom rb.set_dev_weight(2, 0.0) # we'll rebalance but can't move any parts rb.rebalance(seed=1) # zero weight tier has one copy of 1/4 part-replica self.assertEqual(rb.dispersion, 75.0) self.assertEqual(rb._dispersion_graph, { (0,): [0, 0, 0, 256], (0, 0): [0, 0, 0, 256], (0, 0, '127.0.0.1'): [0, 0, 0, 256], (0, 0, '127.0.0.1', 0): [64, 192, 0, 0], (0, 0, '127.0.0.1', 1): [64, 192, 0, 0], (0, 0, '127.0.0.1', 2): [64, 192, 0, 0], (0, 0, '127.0.0.1', 3): [64, 192, 0, 0], }) # unlock the stuck parts rb.pretend_min_part_hours_passed() rb.rebalance(seed=3) self.assertEqual(rb.dispersion, 0.0) self.assertEqual(rb._dispersion_graph, { (0,): [0, 0, 0, 256], (0, 0): [0, 0, 0, 256], (0, 0, '127.0.0.1'): [0, 0, 0, 256], (0, 0, '127.0.0.1', 0): [0, 256, 0, 0], (0, 0, '127.0.0.1', 1): [0, 256, 0, 0], (0, 0, '127.0.0.1', 3): [0, 256, 0, 0], }) def test_effective_overload(self): rb = ring.RingBuilder(8, 3, 1) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) # z1 rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) # z2 rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) # this ring requires overload required = rb.get_required_overload() self.assertGreater(required, 0.1) # and we'll use a little bit rb.set_overload(0.1) rb.rebalance(seed=7) rb.validate() # but with-out enough overload we're not dispersed self.assertGreater(rb.dispersion, 0) # add the other dev to z2 rb.add_dev({'id': 8, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdc'}) # but also fail another device in the same! rb.remove_dev(6) # we still require overload required = rb.get_required_overload() self.assertGreater(required, 0.1) rb.pretend_min_part_hours_passed() rb.rebalance(seed=7) rb.validate() # ... and without enough we're full dispersed self.assertGreater(rb.dispersion, 0) # ok, let's fix z2's weight for real rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) # ... technically, we no longer require overload self.assertEqual(rb.get_required_overload(), 0.0) # so let's rebalance w/o resetting min_part_hours rb.rebalance(seed=7) rb.validate() # ... and that got it in one pass boo-yah! self.assertEqual(rb.dispersion, 0) def zone_weights_over_device_count(self): rb = ring.RingBuilder(8, 3, 1) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) # z1 rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) # z2 rb.add_dev({'id': 2, 'region': 0, 'zone': 2, 'weight': 200, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.rebalance(seed=7) rb.validate() self.assertEqual(rb.dispersion, 0) self.assertAlmostEqual(rb.get_balance(), (1.0 / 3.0) * 100) def test_more_devices_than_replicas_validation_when_removed_dev(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sdc'}) rb.rebalance() rb.remove_dev(2) with self.assertRaises(ValueError) as e: rb.set_dev_weight(2, 1) msg = "Can not set weight of dev_id 2 because it is marked " \ "for removal" self.assertIn(msg, str(e.exception)) with self.assertRaises(exceptions.RingValidationError) as e: rb.rebalance() msg = 'Replica count of 3 requires more than 2 devices' self.assertIn(msg, str(e.exception)) def _add_dev_delete_first_n(self, add_dev_count, n): rb = ring.RingBuilder(8, 3, 1) dev_names = ['sda', 'sdb', 'sdc', 'sdd', 'sde', 'sdf'] for i in range(add_dev_count): if i < len(dev_names): dev_name = dev_names[i] else: dev_name = 'sda' rb.add_dev({'id': i, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': dev_name}) rb.rebalance() if (n > 0): rb.pretend_min_part_hours_passed() # remove first n for i in range(n): rb.remove_dev(i) rb.pretend_min_part_hours_passed() rb.rebalance() return rb def test_reuse_of_dev_holes_without_id(self): # try with contiguous holes at beginning add_dev_count = 6 rb = self._add_dev_delete_first_n(add_dev_count, add_dev_count - 3) new_dev_id = rb.add_dev({'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) self.assertLess(new_dev_id, add_dev_count) # try with non-contiguous holes # [0, 1, None, 3, 4, None] rb2 = ring.RingBuilder(8, 3, 1) for i in range(6): rb2.add_dev({'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) rb2.rebalance() rb2.pretend_min_part_hours_passed() rb2.remove_dev(2) rb2.remove_dev(5) rb2.pretend_min_part_hours_passed() rb2.rebalance() first = rb2.add_dev({'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) second = rb2.add_dev({'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) # add a new one (without reusing a hole) third = rb2.add_dev({'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) self.assertEqual(first, 2) self.assertEqual(second, 5) self.assertEqual(third, 6) def test_reuse_of_dev_holes_with_id(self): add_dev_count = 6 rb = self._add_dev_delete_first_n(add_dev_count, add_dev_count - 3) # add specifying id exp_new_dev_id = 2 # [dev, dev, None, dev, dev, None] try: new_dev_id = rb.add_dev({'id': exp_new_dev_id, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'weight': 1.0, 'device': 'sda'}) self.assertEqual(new_dev_id, exp_new_dev_id) except exceptions.DuplicateDeviceError: self.fail("device hole not reused") def test_increase_partition_power(self): rb = ring.RingBuilder(8, 3.0, 1) self.assertEqual(rb.part_power, 8) # add more devices than replicas to the ring for i in range(10): dev = "sdx%s" % i rb.add_dev({'id': i, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': dev}) rb.rebalance(seed=1) # Let's save the ring, and get the nodes for an object ring_file = os.path.join(self.testdir, 'test_partpower.ring.gz') rd = rb.get_ring() rd.save(ring_file) r = ring.Ring(ring_file) old_part, old_nodes = r.get_nodes("acc", "cont", "obj") old_version = rb.version rb.increase_partition_power() rb.validate() changed_parts, _balance, removed_devs = rb.rebalance() self.assertEqual(changed_parts, 0) self.assertEqual(removed_devs, 0) old_ring = r rd = rb.get_ring() rd.save(ring_file) r = ring.Ring(ring_file) new_part, new_nodes = r.get_nodes("acc", "cont", "obj") # sanity checks self.assertEqual(rb.part_power, 9) self.assertEqual(rb.version, old_version + 2) # make sure there is always the same device assigned to every pair of # partitions for replica in rb._replica2part2dev: for part in range(0, len(replica), 2): dev = replica[part] next_dev = replica[part + 1] self.assertEqual(dev, next_dev) # same for last_part moves for part in range(0, rb.parts, 2): this_last_moved = rb._last_part_moves[part] next_last_moved = rb._last_part_moves[part + 1] self.assertEqual(this_last_moved, next_last_moved) for i in range(100): suffix = uuid.uuid4() account = 'account_%s' % suffix container = 'container_%s' % suffix obj = 'obj_%s' % suffix old_part, old_nodes = old_ring.get_nodes(account, container, obj) new_part, new_nodes = r.get_nodes(account, container, obj) # Due to the increased partition power, the partition each object # is assigned to has changed. If the old partition was X, it will # now be either located in 2*X or 2*X+1 self.assertIn(new_part, [old_part * 2, old_part * 2 + 1]) # Importantly, we expect the objects to be placed on the same # nodes after increasing the partition power self.assertEqual(old_nodes, new_nodes) class TestGetRequiredOverload(unittest.TestCase): maxDiff = None def test_none_needed(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 1, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) # 4 equal-weight devs and 3 replicas: this can be balanced without # resorting to overload at all self.assertAlmostEqual(rb.get_required_overload(), 0) expected = { (0, 0, '127.0.0.1', 0): 0.75, (0, 0, '127.0.0.1', 1): 0.75, (0, 0, '127.0.0.1', 2): 0.75, (0, 0, '127.0.0.1', 3): 0.75, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, { tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 4}) wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 4}) # since no overload is needed, target_replicas is the same rb.set_overload(0.10) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) # ... no matter how high you go! rb.set_overload(100.0) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) # 3 equal-weight devs and 3 replicas: this can also be balanced rb.remove_dev(3) self.assertAlmostEqual(rb.get_required_overload(), 0) expected = { (0, 0, '127.0.0.1', 0): 1.0, (0, 0, '127.0.0.1', 1): 1.0, (0, 0, '127.0.0.1', 2): 1.0, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 4}) wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 4}) # ... still no overload rb.set_overload(100.0) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) def test_equal_replica_and_devices_count_ignore_weights(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 7.47, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 5.91, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 6.44, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) expected = { 0: 1.0, 1: 1.0, 2: 1.0, } # simplicity itself self.assertEqual(expected, { t[-1]: r for (t, r) in rb._build_weighted_replicas_by_tier().items() if len(t) == 4}) self.assertEqual(expected, { t[-1]: r for (t, r) in rb._build_wanted_replicas_by_tier().items() if len(t) == 4}) self.assertEqual(expected, { t[-1]: r for (t, r) in rb._build_target_replicas_by_tier().items() if len(t) == 4}) # ... no overload required! self.assertEqual(0, rb.get_required_overload()) rb.rebalance() expected = { 0: 256, 1: 256, 2: 256, } self.assertEqual(expected, {d['id']: d['parts'] for d in rb._iter_devs()}) def test_small_zone(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 4, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 4, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 4, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 4, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 3, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) expected = { (0, 0): 1.0434782608695652, (0, 1): 1.0434782608695652, (0, 2): 0.9130434782608695, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) expected = { (0, 0): 1.0, (0, 1): 1.0, (0, 2): 1.0, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) # the device tier is interesting because one of the devices in zone # two has a different weight expected = { 0: 0.5217391304347826, 1: 0.5217391304347826, 2: 0.5217391304347826, 3: 0.5217391304347826, 4: 0.5217391304347826, 5: 0.3913043478260869, } self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 4}) # ... but, each pair of devices still needs to hold a whole # replicanth; which we'll try distribute fairly among devices in # zone 2, so that they can share the burden and ultimately the # required overload will be as small as possible. expected = { 0: 0.5, 1: 0.5, 2: 0.5, 3: 0.5, 4: 0.5714285714285715, 5: 0.42857142857142855, } self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 4}) # full dispersion requires zone two's devices to eat more than # they're weighted for self.assertAlmostEqual(rb.get_required_overload(), 0.095238, delta=1e-5) # so... if we give it enough overload it we should get full dispersion rb.set_overload(0.1) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) def test_multiple_small_zones(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 150, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 150, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 10, 'region': 0, 'zone': 1, 'weight': 150, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 3, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 3, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) expected = { (0, 0): 2.1052631578947367, (0, 1): 0.47368421052631576, (0, 2): 0.21052631578947367, (0, 3): 0.21052631578947367, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) # without any overload, we get weight target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: r for (tier, r) in target_replicas.items() if len(tier) == 2}) expected = { (0, 0): 1.0, (0, 1): 1.0, (0, 2): 0.49999999999999994, (0, 3): 0.49999999999999994, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {t: r for (t, r) in wanted_replicas.items() if len(t) == 2}) self.assertEqual(1.3750000000000002, rb.get_required_overload()) # with enough overload we get the full dispersion rb.set_overload(1.5) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: r for (tier, r) in target_replicas.items() if len(tier) == 2}) # with not enough overload, we get somewhere in the middle rb.set_overload(1.0) expected = { (0, 0): 1.3014354066985647, (0, 1): 0.8564593301435406, (0, 2): 0.4210526315789473, (0, 3): 0.4210526315789473, } target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: r for (tier, r) in target_replicas.items() if len(tier) == 2}) def test_big_zone(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 60, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 60, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 3, 'weight': 60, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 3, 'weight': 60, 'ip': '127.0.0.3', 'port': 10000, 'device': 'sdb'}) expected = { (0, 0): 1.0714285714285714, (0, 1): 0.6428571428571429, (0, 2): 0.6428571428571429, (0, 3): 0.6428571428571429, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) expected = { (0, 0): 1.0, (0, 1): 0.6666666666666667, (0, 2): 0.6666666666666667, (0, 3): 0.6666666666666667, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) # when all the devices and servers in a zone are evenly weighted # it will accurately proxy their required overload, all the # zones besides 0 require the same overload t = random.choice([t for t in weighted_replicas if len(t) == 2 and t[1] != 0]) expected_overload = ((wanted_replicas[t] - weighted_replicas[t]) / weighted_replicas[t]) self.assertAlmostEqual(rb.get_required_overload(), expected_overload) # but if you only give it out half of that rb.set_overload(expected_overload / 2.0) # ... you can expect it's not going to full disperse expected = { (0, 0): 1.0357142857142856, (0, 1): 0.6547619047619049, (0, 2): 0.6547619047619049, (0, 3): 0.6547619047619049, } target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 2}) def test_enormous_zone(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 500, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'weight': 60, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 60, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 2, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 3, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 9, 'region': 0, 'zone': 3, 'weight': 60, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) expected = { (0, 0): 2.542372881355932, (0, 1): 0.15254237288135591, (0, 2): 0.15254237288135591, (0, 3): 0.15254237288135591, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) expected = { (0, 0): 1.0, (0, 1): 0.6666666666666667, (0, 2): 0.6666666666666667, (0, 3): 0.6666666666666667, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) # ouch, those "tiny" devices need to hold 3x more than their # weighted for! self.assertAlmostEqual(rb.get_required_overload(), 3.370370, delta=1e-5) # let's get a little crazy, and let devices eat up to 1x more than # their capacity is weighted for - see how far that gets us... rb.set_overload(1) target_replicas = rb._build_target_replicas_by_tier() expected = { (0, 0): 2.084745762711864, (0, 1): 0.30508474576271183, (0, 2): 0.30508474576271183, (0, 3): 0.30508474576271183, } self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 2}) def test_two_big_two_small(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 100, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': 100, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'weight': 45, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'weight': 45, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 3, 'weight': 35, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 3, 'weight': 35, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) expected = { (0, 0): 1.0714285714285714, (0, 1): 1.0714285714285714, (0, 2): 0.48214285714285715, (0, 3): 0.375, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) expected = { (0, 0): 1.0, (0, 1): 1.0, (0, 2): 0.5625, (0, 3): 0.43749999999999994, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) # I'm not sure it's significant or coincidental that the devices # in zone 2 & 3 who end up splitting the 3rd replica turn out to # need to eat ~1/6th extra replicanths self.assertAlmostEqual(rb.get_required_overload(), 1.0 / 6.0) # ... *so* 10% isn't *quite* enough rb.set_overload(0.1) target_replicas = rb._build_target_replicas_by_tier() expected = { (0, 0): 1.0285714285714285, (0, 1): 1.0285714285714285, (0, 2): 0.5303571428571429, (0, 3): 0.4125, } self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 2}) # ... but 20% will do the trick! rb.set_overload(0.2) target_replicas = rb._build_target_replicas_by_tier() expected = { (0, 0): 1.0, (0, 1): 1.0, (0, 2): 0.5625, (0, 3): 0.43749999999999994, } self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 2}) def test_multiple_replicas_each(self): rb = ring.RingBuilder(8, 7, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': 80, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': 80, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'weight': 80, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'weight': 80, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sdd'}) rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'weight': 80, 'ip': '127.0.0.0', 'port': 10000, 'device': 'sde'}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'weight': 70, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'weight': 70, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdb'}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'weight': 70, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdc'}) rb.add_dev({'id': 8, 'region': 0, 'zone': 1, 'weight': 70, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sdd'}) expected = { (0, 0): 4.117647058823529, (0, 1): 2.8823529411764706, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) expected = { (0, 0): 4.0, (0, 1): 3.0, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) # I guess 2.88 => 3.0 is about a 4% increase self.assertAlmostEqual(rb.get_required_overload(), 0.040816326530612256) # ... 10% is plenty enough here rb.set_overload(0.1) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 2}) def test_small_extra_server_in_zone_with_multiple_replicas(self): rb = ring.RingBuilder(8, 5, 1) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 1000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdb', 'weight': 1000}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdc', 'weight': 1000}) # z1 rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 1000}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdb', 'weight': 1000}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdc', 'weight': 1000}) # z1 - extra small server rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sda', 'weight': 50}) expected = { (0, 0): 2.479338842975207, (0, 1): 2.5206611570247937, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {t: r for (t, r) in weighted_replicas.items() if len(t) == 2}) # dispersion is fine with this at the zone tier wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {t: r for (t, r) in wanted_replicas.items() if len(t) == 2}) # ... but not ok with that tiny server expected = { '127.0.0.1': 2.479338842975207, '127.0.0.2': 1.5206611570247937, '127.0.0.3': 1.0, } self.assertEqual(expected, {t[-1]: r for (t, r) in wanted_replicas.items() if len(t) == 3}) self.assertAlmostEqual(23.2, rb.get_required_overload()) def test_multiple_replicas_in_zone_with_single_device(self): rb = ring.RingBuilder(8, 5, 0) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 100}) # z1 rb.add_dev({'id': 1, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sdb', 'weight': 100}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sdc', 'weight': 100}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sdd', 'weight': 100}) # first things first, make sure we do this right rb.rebalance() # each device get's a sing replica of every part expected = { 0: 256, 1: 256, 2: 256, 3: 256, 4: 256, } self.assertEqual(expected, {d['id']: d['parts'] for d in rb._iter_devs()}) # but let's make sure we're thinking about it right too expected = { 0: 1.0, 1: 1.0, 2: 1.0, 3: 1.0, 4: 1.0, } # by weight everyone is equal weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in weighted_replicas.items() if len(t) == 4}) # wanted might have liked to have fewer replicas in z1, but the # single device in z0 limits us one replica per device with rb.debug(): wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in wanted_replicas.items() if len(t) == 4}) # even with some overload - still one replica per device rb.set_overload(1.0) target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in target_replicas.items() if len(t) == 4}) # when overload can not change the outcome none is required self.assertEqual(0.0, rb.get_required_overload()) # even though dispersion is terrible (in z1 particularly) self.assertEqual(100.0, rb.dispersion) def test_one_big_guy_does_not_spoil_his_buddy(self): rb = ring.RingBuilder(8, 3, 0) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 100}) # z1 rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sda', 'weight': 100}) # z2 rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'ip': '127.0.2.1', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'ip': '127.0.2.2', 'port': 6200, 'device': 'sda', 'weight': 10000}) # obviously d5 gets one whole replica; the other two replicas # are split evenly among the five other devices # (i.e. ~0.4 replicanths for each 100 units of weight) expected = { 0: 0.39999999999999997, 1: 0.39999999999999997, 2: 0.39999999999999997, 3: 0.39999999999999997, 4: 0.39999999999999997, 5: 1.0, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in weighted_replicas.items() if len(t) == 4}) # with no overload we get the "balanced" placement target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in target_replicas.items() if len(t) == 4}) # but in reality, these devices having such disparate weights # leads to a *terrible* balance even w/o overload! rb.rebalance(seed=9) self.assertEqual(rb.get_balance(), 1308.2031249999998) # even though part assignment is pretty reasonable expected = { 0: 103, 1: 102, 2: 103, 3: 102, 4: 102, 5: 256, } self.assertEqual(expected, { d['id']: d['parts'] for d in rb._iter_devs()}) # so whats happening is the small devices are holding *way* more # *real* parts than their *relative* portion of the weight would # like them too! expected = { 0: 1308.2031249999998, 1: 1294.5312499999998, 2: 1308.2031249999998, 3: 1294.5312499999998, 4: 1294.5312499999998, 5: -65.0, } self.assertEqual(expected, rb._build_balance_per_dev()) # increasing overload moves towards one replica in each tier rb.set_overload(0.20) expected = { 0: 0.48, 1: 0.48, 2: 0.48, 3: 0.48, 4: 0.30857142857142855, 5: 0.7714285714285714, } target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in target_replicas.items() if len(t) == 4}) # ... and as always increasing overload makes balance *worse* rb.rebalance(seed=17) self.assertEqual(rb.get_balance(), 1581.6406249999998) # but despite the overall trend toward imbalance, in the tier # with the huge device, the small device is trying to shed parts # as effectively as it can (which would be useful if it was the # only small device isolated in a tier with other huge devices # trying to gobble up all the replicanths in the tier - see # `test_one_small_guy_does_not_spoil_his_buddy`!) expected = { 0: 123, 1: 123, 2: 123, 3: 123, 4: 79, 5: 197, } self.assertEqual(expected, { d['id']: d['parts'] for d in rb._iter_devs()}) # *see*, at least *someones* balance is getting better! expected = { 0: 1581.6406249999998, 1: 1581.6406249999998, 2: 1581.6406249999998, 3: 1581.6406249999998, 4: 980.078125, 5: -73.06640625, } self.assertEqual(expected, rb._build_balance_per_dev()) def test_one_small_guy_does_not_spoil_his_buddy(self): rb = ring.RingBuilder(8, 3, 0) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 10000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 10000}) # z1 rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sda', 'weight': 10000}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sda', 'weight': 10000}) # z2 rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'ip': '127.0.2.1', 'port': 6200, 'device': 'sda', 'weight': 10000}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'ip': '127.0.2.2', 'port': 6200, 'device': 'sda', 'weight': 100}) # it's almost like 3.0 / 5 ~= 0.6, but that one little guy get's # his fair share expected = { 0: 0.5988023952095808, 1: 0.5988023952095808, 2: 0.5988023952095808, 3: 0.5988023952095808, 4: 0.5988023952095808, 5: 0.005988023952095809, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in weighted_replicas.items() if len(t) == 4}) # with no overload we get a nice balanced placement target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in target_replicas.items() if len(t) == 4}) rb.rebalance(seed=9) # part placement looks goods expected = { 0: 154, 1: 153, 2: 153, 3: 153, 4: 153, 5: 2, } self.assertEqual(expected, { d['id']: d['parts'] for d in rb._iter_devs()}) # ... balance is a little lumpy on the small guy since he wants # one and a half parts :\ expected = { 0: 0.4609375000000142, 1: -0.1914062499999858, 2: -0.1914062499999858, 3: -0.1914062499999858, 4: -0.1914062499999858, 5: 30.46875, } self.assertEqual(expected, rb._build_balance_per_dev()) self.assertEqual(rb.get_balance(), 30.46875) # increasing overload moves towards one replica in each tier rb.set_overload(0.5) expected = { 0: 0.5232035928143712, 1: 0.5232035928143712, 2: 0.5232035928143712, 3: 0.5232035928143712, 4: 0.8982035928143712, 5: 0.008982035928143714, } target_replicas = rb._build_target_replicas_by_tier() self.assertEqual(expected, {t[-1]: r for (t, r) in target_replicas.items() if len(t) == 4}) # ... and as always increasing overload makes balance *worse* rb.rebalance(seed=17) self.assertEqual(rb.get_balance(), 95.703125) # but despite the overall trend toward imbalance, the little guy # isn't really taking on many new parts! expected = { 0: 134, 1: 134, 2: 134, 3: 133, 4: 230, 5: 3, } self.assertEqual(expected, { d['id']: d['parts'] for d in rb._iter_devs()}) # *see*, at everyone's balance is getting worse *together*! expected = { 0: -12.585937499999986, 1: -12.585937499999986, 2: -12.585937499999986, 3: -13.238281249999986, 4: 50.0390625, 5: 95.703125, } self.assertEqual(expected, rb._build_balance_per_dev()) def test_two_servers_with_more_than_one_replica(self): rb = ring.RingBuilder(8, 3, 0) # z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 60}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 60}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sda', 'weight': 60}) # z1 rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sda', 'weight': 80}) rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sda', 'weight': 128}) # z2 rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'ip': '127.0.2.1', 'port': 6200, 'device': 'sda', 'weight': 80}) rb.add_dev({'id': 6, 'region': 0, 'zone': 2, 'ip': '127.0.2.2', 'port': 6200, 'device': 'sda', 'weight': 240}) rb.set_overload(0.1) rb.rebalance() self.assertEqual(12.161458333333343, rb.get_balance()) replica_plan = rb._build_target_replicas_by_tier() for dev in rb._iter_devs(): tier = (dev['region'], dev['zone'], dev['ip'], dev['id']) expected_parts = replica_plan[tier] * rb.parts self.assertAlmostEqual(dev['parts'], expected_parts, delta=1) def test_multi_zone_with_failed_device(self): rb = ring.RingBuilder(8, 3, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdb', 'weight': 2000}) rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdb', 'weight': 2000}) rb.add_dev({'id': 4, 'region': 0, 'zone': 2, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 5, 'region': 0, 'zone': 2, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sdb', 'weight': 2000}) # sanity, balanced and dispersed expected = { (0, 0): 1.0, (0, 1): 1.0, (0, 2): 1.0, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 2}) self.assertEqual(rb.get_required_overload(), 0.0) # fail a device in zone 2 rb.remove_dev(4) expected = { 0: 0.6, 1: 0.6, 2: 0.6, 3: 0.6, 5: 0.6, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 4}) expected = { 0: 0.5, 1: 0.5, 2: 0.5, 3: 0.5, 5: 1.0, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 4}) # does this make sense? every zone was holding 1/3rd of the # replicas, so each device was 1/6th, remove a device and # suddenly it's holding *both* sixths which is 2/3rds? self.assertAlmostEqual(rb.get_required_overload(), 2.0 / 3.0) # 10% isn't nearly enough rb.set_overload(0.1) target_replicas = rb._build_target_replicas_by_tier() expected = { 0: 0.585, 1: 0.585, 2: 0.585, 3: 0.585, 5: 0.6599999999999999, } self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) # 50% isn't even enough rb.set_overload(0.5) target_replicas = rb._build_target_replicas_by_tier() expected = { 0: 0.525, 1: 0.525, 2: 0.525, 3: 0.525, 5: 0.8999999999999999, } self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) # even 65% isn't enough (but it's getting closer) rb.set_overload(0.65) target_replicas = rb._build_target_replicas_by_tier() expected = { 0: 0.5025000000000001, 1: 0.5025000000000001, 2: 0.5025000000000001, 3: 0.5025000000000001, 5: 0.99, } self.assertEqual(expected, {tier[3]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 4}) def test_balanced_zones_unbalanced_servers(self): rb = ring.RingBuilder(8, 3, 1) # zone 0 server 127.0.0.1 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 3000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdb', 'weight': 3000}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 3000}) # zone 1 server 127.0.0.2 rb.add_dev({'id': 4, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 4000}) rb.add_dev({'id': 5, 'region': 0, 'zone': 1, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdb', 'weight': 4000}) # zone 1 (again) server 127.0.0.3 rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sda', 'weight': 1000}) weighted_replicas = rb._build_weighted_replicas_by_tier() # zones are evenly weighted expected = { (0, 0): 1.5, (0, 1): 1.5, } self.assertEqual(expected, {tier: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 2}) # ... but servers are not expected = { '127.0.0.1': 1.5, '127.0.0.2': 1.3333333333333333, '127.0.0.3': 0.16666666666666666, } self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 3}) # make sure wanted will even it out expected = { '127.0.0.1': 1.5, '127.0.0.2': 1.0, '127.0.0.3': 0.4999999999999999, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 3}) # so it wants 1/6th and eats 1/2 - that's 2/6ths more than it # wants which is a 200% increase self.assertAlmostEqual(rb.get_required_overload(), 2.0) # the overload doesn't effect the tiers that are already dispersed rb.set_overload(1) target_replicas = rb._build_target_replicas_by_tier() expected = { '127.0.0.1': 1.5, # notice with half the overload 1/6th replicanth swapped servers '127.0.0.2': 1.1666666666666665, '127.0.0.3': 0.3333333333333333, } self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 3}) def test_adding_second_zone(self): rb = ring.RingBuilder(3, 3, 1) # zone 0 server 127.0.0.1 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdb', 'weight': 2000}) # zone 0 server 127.0.0.2 rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdb', 'weight': 2000}) # zone 0 server 127.0.0.3 rb.add_dev({'id': 4, 'region': 0, 'zone': 0, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 5, 'region': 0, 'zone': 0, 'ip': '127.0.0.3', 'port': 6200, 'device': 'sdb', 'weight': 2000}) # sanity, balanced and dispersed expected = { '127.0.0.1': 1.0, '127.0.0.2': 1.0, '127.0.0.3': 1.0, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 3}) wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 3}) self.assertEqual(rb.get_required_overload(), 0) # start adding a second zone # zone 1 server 127.0.1.1 rb.add_dev({'id': 6, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 7, 'region': 0, 'zone': 1, 'ip': '127.0.1.1', 'port': 6200, 'device': 'sdb', 'weight': 100}) # zone 1 server 127.0.1.2 rb.add_dev({'id': 8, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 9, 'region': 0, 'zone': 1, 'ip': '127.0.1.2', 'port': 6200, 'device': 'sdb', 'weight': 100}) # zone 1 server 127.0.1.3 rb.add_dev({'id': 10, 'region': 0, 'zone': 1, 'ip': '127.0.1.3', 'port': 6200, 'device': 'sda', 'weight': 100}) rb.add_dev({'id': 11, 'region': 0, 'zone': 1, 'ip': '127.0.1.3', 'port': 6200, 'device': 'sdb', 'weight': 100}) # this messes things up pretty royally expected = { '127.0.0.1': 0.9523809523809523, '127.0.0.2': 0.9523809523809523, '127.0.0.3': 0.9523809523809523, '127.0.1.1': 0.047619047619047616, '127.0.1.2': 0.047619047619047616, '127.0.1.3': 0.047619047619047616, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 3}) expected = { '127.0.0.1': 0.6666666666666667, '127.0.0.2': 0.6666666666666667, '127.0.0.3': 0.6666666666666667, '127.0.1.1': 0.3333333333333333, '127.0.1.2': 0.3333333333333333, '127.0.1.3': 0.3333333333333333, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in wanted_replicas.items() if len(tier) == 3}) # so dispersion would require these devices hold 6x more than # prescribed by weight, defeating any attempt at gradually # anything self.assertAlmostEqual(rb.get_required_overload(), 6.0) # so let's suppose we only allow for 10% overload rb.set_overload(0.10) target_replicas = rb._build_target_replicas_by_tier() expected = { # we expect servers in zone 0 to be between 0.952 and 0.666 '127.0.0.1': 0.9476190476190476, '127.0.0.2': 0.9476190476190476, '127.0.0.3': 0.9476190476190476, # we expect servers in zone 1 to be between 0.0476 and 0.333 # and in fact its ~10% increase (very little compared to 6x!) '127.0.1.1': 0.052380952380952375, '127.0.1.2': 0.052380952380952375, '127.0.1.3': 0.052380952380952375, } self.assertEqual(expected, {tier[2]: weighted for (tier, weighted) in target_replicas.items() if len(tier) == 3}) def test_gradual_replica_count(self): rb = ring.RingBuilder(3, 2.5, 1) rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'ip': '127.0.0.1', 'port': 6200, 'device': 'sdb', 'weight': 2000}) rb.add_dev({'id': 2, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sda', 'weight': 2000}) rb.add_dev({'id': 3, 'region': 0, 'zone': 0, 'ip': '127.0.0.2', 'port': 6200, 'device': 'sdb', 'weight': 2000}) expected = { 0: 0.625, 1: 0.625, 2: 0.625, 3: 0.625, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, { tier[3]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 4}) wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, { tier[3]: wanted for (tier, wanted) in wanted_replicas.items() if len(tier) == 4}) self.assertEqual(rb.get_required_overload(), 0) # server 127.0.0.2 will have only one device rb.remove_dev(2) # server 127.0.0.1 has twice the capacity of 127.0.0.2 expected = { '127.0.0.1': 1.6666666666666667, '127.0.0.2': 0.8333333333333334, } weighted_replicas = rb._build_weighted_replicas_by_tier() self.assertEqual(expected, { tier[2]: weighted for (tier, weighted) in weighted_replicas.items() if len(tier) == 3}) # dispersion requirements extend only to whole replicas expected = { '127.0.0.1': 1.4999999999999998, '127.0.0.2': 1.0, } wanted_replicas = rb._build_wanted_replicas_by_tier() self.assertEqual(expected, { tier[2]: wanted for (tier, wanted) in wanted_replicas.items() if len(tier) == 3}) # 5/6ths to a whole replicanth is a 20% increase self.assertAlmostEqual(rb.get_required_overload(), 0.2) # so let's suppose we only allow for 10% overload rb.set_overload(0.1) target_replicas = rb._build_target_replicas_by_tier() expected = { '127.0.0.1': 1.5833333333333333, '127.0.0.2': 0.9166666666666667, } self.assertEqual(expected, { tier[2]: wanted for (tier, wanted) in target_replicas.items() if len(tier) == 3}) def test_perfect_four_zone_four_replica_bad_placement(self): rb = ring.RingBuilder(4, 4, 1) # this weight is sorta nuts, but it's really just to help the # weight_of_one_part hit a magic number where floats mess up # like they would on ring with a part power of 19 and 100's of # 1000's of units of weight. weight = 21739130434795e-11 # r0z0 rb.add_dev({'id': 0, 'region': 0, 'zone': 0, 'weight': weight, 'ip': '127.0.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 1, 'region': 0, 'zone': 0, 'weight': weight, 'ip': '127.0.0.2', 'port': 10000, 'device': 'sdb'}) # r0z1 rb.add_dev({'id': 2, 'region': 0, 'zone': 1, 'weight': weight, 'ip': '127.0.1.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 3, 'region': 0, 'zone': 1, 'weight': weight, 'ip': '127.0.1.2', 'port': 10000, 'device': 'sdb'}) # r1z0 rb.add_dev({'id': 4, 'region': 1, 'zone': 0, 'weight': weight, 'ip': '127.1.0.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 5, 'region': 1, 'zone': 0, 'weight': weight, 'ip': '127.1.0.2', 'port': 10000, 'device': 'sdb'}) # r1z1 rb.add_dev({'id': 6, 'region': 1, 'zone': 1, 'weight': weight, 'ip': '127.1.1.1', 'port': 10000, 'device': 'sda'}) rb.add_dev({'id': 7, 'region': 1, 'zone': 1, 'weight': weight, 'ip': '127.1.1.2', 'port': 10000, 'device': 'sdb'}) # the replica plan is sound expectations = { # tier_len => expected replicas 1: { (0,): 2.0, (1,): 2.0, }, 2: { (0, 0): 1.0, (0, 1): 1.0, (1, 0): 1.0, (1, 1): 1.0, } } wr = rb._build_replica_plan() for tier_len, expected in expectations.items(): self.assertEqual(expected, {t: r['max'] for (t, r) in wr.items() if len(t) == tier_len}) # even thought a naive ceil of weights is surprisingly wrong expectations = { # tier_len => expected replicas 1: { (0,): 3.0, (1,): 3.0, }, 2: { (0, 0): 2.0, (0, 1): 2.0, (1, 0): 2.0, (1, 1): 2.0, } } wr = rb._build_weighted_replicas_by_tier() for tier_len, expected in expectations.items(): self.assertEqual(expected, {t: ceil(r) for (t, r) in wr.items() if len(t) == tier_len}) if __name__ == '__main__': unittest.main()