swift/test/unit/common/ring/test_ring.py
Samuel Merritt 6d77c379bd Let admins add a region without melting their cluster
Prior to this commit, swift-ring-builder would place partitions on
devices by first going for maximal dispersion and breaking ties with
device weight. This commit flips the order so that device weight
trumps dispersion.

Note: if your ring can be balanced, you won't see a behavior
change. It's only when device weights and maximal-dispersion come into
conflict that this commit changes anything.

Example: a cluster with two regions. Region 1 has a combined weight of
1000, while region 2 has a combined weight of only 400. The ring has 3
replicas and 2^16 partitions.

Prior to this commit, the balance would look like so:

  Region 1: 2 * 2^16 partitions
  Region 2: 2^16 partitions

After this commit, the balance will be:

  Region 1: 10/14 * 2^16 partitions  (more than before)
  Region 2: 4/14 * 2^16 partitions  (fewer than before)

One consequence of this is that some partitions will not have a
replica in region 2, since it's not big enough to hold all of them.

This way, a cluster operator can add a new region to a single-region
cluster in a gradual fashion so as not to destroy their WAN link with
replication traffic. As device weights are increased in the second
region, more replicas will shift over to it. Once its weight is half
that of the first region's, every partition will have a replica there.

DocImpact

Change-Id: I945abcc4a2917bb12be554b640f7507dd23cd0da
2014-08-21 08:56:29 -07:00

758 lines
34 KiB
Python

# 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 array
import cPickle as pickle
import os
import sys
import unittest
import stat
from contextlib import closing
from gzip import GzipFile
from tempfile import mkdtemp
from shutil import rmtree
from time import sleep, time
from swift.common import ring, utils
class TestRingBase(unittest.TestCase):
def setUp(self):
self._orig_hash_suffix = utils.HASH_PATH_SUFFIX
self._orig_hash_prefix = utils.HASH_PATH_PREFIX
utils.HASH_PATH_SUFFIX = 'endcap'
utils.HASH_PATH_PREFIX = ''
def tearDown(self):
utils.HASH_PATH_SUFFIX = self._orig_hash_suffix
utils.HASH_PATH_PREFIX = self._orig_hash_prefix
class TestRingData(unittest.TestCase):
def setUp(self):
self.testdir = os.path.join(os.path.dirname(__file__), 'ring_data')
rmtree(self.testdir, ignore_errors=1)
os.mkdir(self.testdir)
def tearDown(self):
rmtree(self.testdir, ignore_errors=1)
def assert_ring_data_equal(self, rd_expected, rd_got):
self.assertEquals(rd_expected._replica2part2dev_id,
rd_got._replica2part2dev_id)
self.assertEquals(rd_expected.devs, rd_got.devs)
self.assertEquals(rd_expected._part_shift, rd_got._part_shift)
def test_attrs(self):
r2p2d = [[0, 1, 0, 1], [0, 1, 0, 1]]
d = [{'id': 0, 'zone': 0, 'region': 0, 'ip': '10.1.1.0', 'port': 7000},
{'id': 1, 'zone': 1, 'region': 1, 'ip': '10.1.1.1', 'port': 7000}]
s = 30
rd = ring.RingData(r2p2d, d, s)
self.assertEquals(rd._replica2part2dev_id, r2p2d)
self.assertEquals(rd.devs, d)
self.assertEquals(rd._part_shift, s)
def test_can_load_pickled_ring_data(self):
rd = ring.RingData(
[[0, 1, 0, 1], [0, 1, 0, 1]],
[{'id': 0, 'zone': 0, 'ip': '10.1.1.0', 'port': 7000},
{'id': 1, 'zone': 1, 'ip': '10.1.1.1', 'port': 7000}],
30)
ring_fname = os.path.join(self.testdir, 'foo.ring.gz')
for p in xrange(pickle.HIGHEST_PROTOCOL):
with closing(GzipFile(ring_fname, 'wb')) as f:
pickle.dump(rd, f, protocol=p)
ring_data = ring.RingData.load(ring_fname)
self.assert_ring_data_equal(rd, ring_data)
def test_roundtrip_serialization(self):
ring_fname = os.path.join(self.testdir, 'foo.ring.gz')
rd = ring.RingData(
[array.array('H', [0, 1, 0, 1]), array.array('H', [0, 1, 0, 1])],
[{'id': 0, 'zone': 0}, {'id': 1, 'zone': 1}], 30)
rd.save(ring_fname)
rd2 = ring.RingData.load(ring_fname)
self.assert_ring_data_equal(rd, rd2)
def test_deterministic_serialization(self):
"""
Two identical rings should produce identical .gz files on disk.
Only true on Python 2.7 or greater.
"""
if sys.version_info[0] == 2 and sys.version_info[1] < 7:
return
os.mkdir(os.path.join(self.testdir, '1'))
os.mkdir(os.path.join(self.testdir, '2'))
# These have to have the same filename (not full path,
# obviously) since the filename gets encoded in the gzip data.
ring_fname1 = os.path.join(self.testdir, '1', 'the.ring.gz')
ring_fname2 = os.path.join(self.testdir, '2', 'the.ring.gz')
rd = ring.RingData(
[array.array('H', [0, 1, 0, 1]), array.array('H', [0, 1, 0, 1])],
[{'id': 0, 'zone': 0}, {'id': 1, 'zone': 1}], 30)
rd.save(ring_fname1)
rd.save(ring_fname2)
with open(ring_fname1) as ring1:
with open(ring_fname2) as ring2:
self.assertEqual(ring1.read(), ring2.read())
def test_permissions(self):
ring_fname = os.path.join(self.testdir, 'stat.ring.gz')
rd = ring.RingData(
[array.array('H', [0, 1, 0, 1]), array.array('H', [0, 1, 0, 1])],
[{'id': 0, 'zone': 0}, {'id': 1, 'zone': 1}], 30)
rd.save(ring_fname)
self.assertEqual(oct(stat.S_IMODE(os.stat(ring_fname).st_mode)),
'0644')
class TestRing(TestRingBase):
def setUp(self):
super(TestRing, self).setUp()
self.testdir = mkdtemp()
self.testgz = os.path.join(self.testdir, 'whatever.ring.gz')
self.intended_replica2part2dev_id = [
array.array('H', [0, 1, 0, 1]),
array.array('H', [0, 1, 0, 1]),
array.array('H', [3, 4, 3, 4])]
self.intended_devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.0.1',
'replication_port': 6066},
{'id': 1, 'region': 0, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.0.2',
'replication_port': 6066},
None,
{'id': 3, 'region': 0, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.1', 'port': 6000,
'replication_ip': '10.2.0.1',
'replication_port': 6066},
{'id': 4, 'region': 0, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.2', 'port': 6000,
'replication_ip': '10.2.0.1',
'replication_port': 6066}]
self.intended_part_shift = 30
self.intended_reload_time = 15
ring.RingData(
self.intended_replica2part2dev_id,
self.intended_devs, self.intended_part_shift).save(self.testgz)
self.ring = ring.Ring(
self.testdir,
reload_time=self.intended_reload_time, ring_name='whatever')
def tearDown(self):
super(TestRing, self).tearDown()
rmtree(self.testdir, ignore_errors=1)
def test_creation(self):
self.assertEquals(self.ring._replica2part2dev_id,
self.intended_replica2part2dev_id)
self.assertEquals(self.ring._part_shift, self.intended_part_shift)
self.assertEquals(self.ring.devs, self.intended_devs)
self.assertEquals(self.ring.reload_time, self.intended_reload_time)
self.assertEquals(self.ring.serialized_path, self.testgz)
# test invalid endcap
_orig_hash_path_suffix = utils.HASH_PATH_SUFFIX
_orig_hash_path_prefix = utils.HASH_PATH_PREFIX
_orig_swift_conf_file = utils.SWIFT_CONF_FILE
try:
utils.HASH_PATH_SUFFIX = ''
utils.HASH_PATH_PREFIX = ''
utils.SWIFT_CONF_FILE = ''
self.assertRaises(SystemExit, ring.Ring, self.testdir, 'whatever')
finally:
utils.HASH_PATH_SUFFIX = _orig_hash_path_suffix
utils.HASH_PATH_PREFIX = _orig_hash_path_prefix
utils.SWIFT_CONF_FILE = _orig_swift_conf_file
def test_has_changed(self):
self.assertEquals(self.ring.has_changed(), False)
os.utime(self.testgz, (time() + 60, time() + 60))
self.assertEquals(self.ring.has_changed(), True)
def test_reload(self):
os.utime(self.testgz, (time() - 300, time() - 300))
self.ring = ring.Ring(self.testdir, reload_time=0.001,
ring_name='whatever')
orig_mtime = self.ring._mtime
self.assertEquals(len(self.ring.devs), 5)
self.intended_devs.append(
{'id': 3, 'region': 0, 'zone': 3, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 9876})
ring.RingData(
self.intended_replica2part2dev_id,
self.intended_devs, self.intended_part_shift).save(self.testgz)
sleep(0.1)
self.ring.get_nodes('a')
self.assertEquals(len(self.ring.devs), 6)
self.assertNotEquals(self.ring._mtime, orig_mtime)
os.utime(self.testgz, (time() - 300, time() - 300))
self.ring = ring.Ring(self.testdir, reload_time=0.001,
ring_name='whatever')
orig_mtime = self.ring._mtime
self.assertEquals(len(self.ring.devs), 6)
self.intended_devs.append(
{'id': 5, 'region': 0, 'zone': 4, 'weight': 1.0,
'ip': '10.5.5.5', 'port': 9876})
ring.RingData(
self.intended_replica2part2dev_id,
self.intended_devs, self.intended_part_shift).save(self.testgz)
sleep(0.1)
self.ring.get_part_nodes(0)
self.assertEquals(len(self.ring.devs), 7)
self.assertNotEquals(self.ring._mtime, orig_mtime)
os.utime(self.testgz, (time() - 300, time() - 300))
self.ring = ring.Ring(self.testdir, reload_time=0.001,
ring_name='whatever')
orig_mtime = self.ring._mtime
part, nodes = self.ring.get_nodes('a')
self.assertEquals(len(self.ring.devs), 7)
self.intended_devs.append(
{'id': 6, 'region': 0, 'zone': 5, 'weight': 1.0,
'ip': '10.6.6.6', 'port': 6000})
ring.RingData(
self.intended_replica2part2dev_id,
self.intended_devs, self.intended_part_shift).save(self.testgz)
sleep(0.1)
self.ring.get_more_nodes(part).next()
self.assertEquals(len(self.ring.devs), 8)
self.assertNotEquals(self.ring._mtime, orig_mtime)
os.utime(self.testgz, (time() - 300, time() - 300))
self.ring = ring.Ring(self.testdir, reload_time=0.001,
ring_name='whatever')
orig_mtime = self.ring._mtime
self.assertEquals(len(self.ring.devs), 8)
self.intended_devs.append(
{'id': 5, 'region': 0, 'zone': 4, 'weight': 1.0,
'ip': '10.5.5.5', 'port': 6000})
ring.RingData(
self.intended_replica2part2dev_id,
self.intended_devs, self.intended_part_shift).save(self.testgz)
sleep(0.1)
self.assertEquals(len(self.ring.devs), 9)
self.assertNotEquals(self.ring._mtime, orig_mtime)
def test_reload_without_replication(self):
replication_less_devs = [{'id': 0, 'region': 0, 'zone': 0,
'weight': 1.0, 'ip': '10.1.1.1',
'port': 6000},
{'id': 1, 'region': 0, 'zone': 0,
'weight': 1.0, 'ip': '10.1.1.1',
'port': 6000},
None,
{'id': 3, 'region': 0, 'zone': 2,
'weight': 1.0, 'ip': '10.1.2.1',
'port': 6000},
{'id': 4, 'region': 0, 'zone': 2,
'weight': 1.0, 'ip': '10.1.2.2',
'port': 6000}]
intended_devs = [{'id': 0, 'region': 0, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.1.1',
'replication_port': 6000},
{'id': 1, 'region': 0, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.1.1',
'replication_port': 6000},
None,
{'id': 3, 'region': 0, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.1', 'port': 6000,
'replication_ip': '10.1.2.1',
'replication_port': 6000},
{'id': 4, 'region': 0, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.2', 'port': 6000,
'replication_ip': '10.1.2.2',
'replication_port': 6000}]
testgz = os.path.join(self.testdir, 'without_replication.ring.gz')
ring.RingData(
self.intended_replica2part2dev_id,
replication_less_devs, self.intended_part_shift).save(testgz)
self.ring = ring.Ring(
self.testdir,
reload_time=self.intended_reload_time,
ring_name='without_replication')
self.assertEquals(self.ring.devs, intended_devs)
def test_reload_old_style_pickled_ring(self):
devs = [{'id': 0, 'zone': 0,
'weight': 1.0, 'ip': '10.1.1.1',
'port': 6000},
{'id': 1, 'zone': 0,
'weight': 1.0, 'ip': '10.1.1.1',
'port': 6000},
None,
{'id': 3, 'zone': 2,
'weight': 1.0, 'ip': '10.1.2.1',
'port': 6000},
{'id': 4, 'zone': 2,
'weight': 1.0, 'ip': '10.1.2.2',
'port': 6000}]
intended_devs = [{'id': 0, 'region': 1, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.1.1',
'replication_port': 6000},
{'id': 1, 'region': 1, 'zone': 0, 'weight': 1.0,
'ip': '10.1.1.1', 'port': 6000,
'replication_ip': '10.1.1.1',
'replication_port': 6000},
None,
{'id': 3, 'region': 1, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.1', 'port': 6000,
'replication_ip': '10.1.2.1',
'replication_port': 6000},
{'id': 4, 'region': 1, 'zone': 2, 'weight': 1.0,
'ip': '10.1.2.2', 'port': 6000,
'replication_ip': '10.1.2.2',
'replication_port': 6000}]
# simulate an old-style pickled ring
testgz = os.path.join(self.testdir,
'without_replication_or_region.ring.gz')
ring_data = ring.RingData(self.intended_replica2part2dev_id,
devs,
self.intended_part_shift)
# an old-style pickled ring won't have region data
for dev in ring_data.devs:
if dev:
del dev["region"]
gz_file = GzipFile(testgz, 'wb')
pickle.dump(ring_data, gz_file, protocol=2)
gz_file.close()
self.ring = ring.Ring(
self.testdir,
reload_time=self.intended_reload_time,
ring_name='without_replication_or_region')
self.assertEquals(self.ring.devs, intended_devs)
def test_get_part(self):
part1 = self.ring.get_part('a')
nodes1 = self.ring.get_part_nodes(part1)
part2, nodes2 = self.ring.get_nodes('a')
self.assertEquals(part1, part2)
self.assertEquals(nodes1, nodes2)
def test_get_part_nodes(self):
part, nodes = self.ring.get_nodes('a')
self.assertEquals(nodes, self.ring.get_part_nodes(part))
def test_get_nodes(self):
# Yes, these tests are deliberately very fragile. We want to make sure
# that if someones changes the results the ring produces, they know it.
self.assertRaises(TypeError, self.ring.get_nodes)
part, nodes = self.ring.get_nodes('a')
self.assertEquals(part, 0)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a1')
self.assertEquals(part, 0)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a4')
self.assertEquals(part, 1)
self.assertEquals(nodes, [self.intended_devs[1],
self.intended_devs[4]])
part, nodes = self.ring.get_nodes('aa')
self.assertEquals(part, 1)
self.assertEquals(nodes, [self.intended_devs[1],
self.intended_devs[4]])
part, nodes = self.ring.get_nodes('a', 'c1')
self.assertEquals(part, 0)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a', 'c0')
self.assertEquals(part, 3)
self.assertEquals(nodes, [self.intended_devs[1],
self.intended_devs[4]])
part, nodes = self.ring.get_nodes('a', 'c3')
self.assertEquals(part, 2)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a', 'c2')
self.assertEquals(part, 2)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a', 'c', 'o1')
self.assertEquals(part, 1)
self.assertEquals(nodes, [self.intended_devs[1],
self.intended_devs[4]])
part, nodes = self.ring.get_nodes('a', 'c', 'o5')
self.assertEquals(part, 0)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a', 'c', 'o0')
self.assertEquals(part, 0)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
part, nodes = self.ring.get_nodes('a', 'c', 'o2')
self.assertEquals(part, 2)
self.assertEquals(nodes, [self.intended_devs[0],
self.intended_devs[3]])
def add_dev_to_ring(self, new_dev):
self.ring.devs.append(new_dev)
self.ring._rebuild_tier_data()
def test_get_more_nodes(self):
# Yes, these tests are deliberately very fragile. We want to make sure
# that if someone changes the results the ring produces, they know it.
exp_part = 6
exp_devs = [48, 93, 96]
exp_zones = set([5, 8, 9])
exp_handoffs = [11, 47, 25, 76, 69, 23, 99, 59, 106, 64, 43, 34, 88, 3,
30, 83, 16, 27, 103, 39, 60, 0, 8, 72, 56, 19, 91, 13,
84, 38, 66, 52, 78, 107, 50, 57, 31, 32, 77, 24, 42,
100, 71, 26, 9, 20, 35, 5, 14, 94, 28, 41, 18, 102,
101, 61, 95, 21, 81, 1, 105, 58, 74, 90, 86, 46, 4, 68,
40, 80, 54, 75, 45, 79, 44, 49, 62, 29, 7, 15, 70, 87,
65, 12, 82, 17, 104, 97, 55, 22, 6, 89, 2, 67, 37, 63,
53, 92, 33, 85, 73, 51, 98, 36, 10]
exp_first_handoffs = [1, 37, 48, 68, 84, 75, 11, 101, 14, 73, 100, 75,
29, 19, 18, 101, 15, 99, 95, 24, 46, 82, 73, 62,
24, 89, 9, 22, 107, 74, 54, 63, 40, 106, 99, 83,
64, 73, 73, 106, 106, 80, 6, 25, 20, 33, 6, 79,
59, 42, 62, 24, 14, 107, 28, 0, 85, 5, 4, 12, 58,
11, 92, 18, 36, 56, 86, 1, 21, 33, 80, 97, 4, 81,
79, 76, 89, 50, 75, 27, 7, 96, 47, 55, 81, 104,
12, 5, 18, 106, 27, 93, 39, 92, 42, 30, 20, 88,
58, 105, 65, 29, 17, 52, 11, 106, 7, 24, 21, 91,
62, 52, 50, 31, 77, 102, 19, 11, 8, 58, 53, 20,
26, 8, 18, 82, 48, 68, 82, 89, 101, 50, 3, 52,
46, 11, 2, 30, 79, 66, 4, 61, 3, 56, 45, 102, 73,
84, 36, 19, 34, 84, 49, 40, 103, 66, 31, 33, 93,
33, 4, 52, 26, 58, 30, 47, 100, 57, 40, 79, 33,
107, 24, 20, 44, 4, 7, 59, 83, 101, 1, 56, 20,
61, 33, 16, 5, 74, 98, 4, 80, 15, 104, 52, 73,
18, 67, 75, 98, 73, 79, 68, 75, 27, 91, 36, 100,
52, 95, 37, 46, 70, 14, 47, 3, 70, 23, 40, 105,
62, 86, 48, 22, 54, 4, 72, 81, 13, 0, 18, 98,
101, 36, 29, 24, 39, 79, 97, 105, 28, 107, 47,
52, 101, 20, 22, 29, 65, 27, 7, 33, 64, 101, 60,
19, 55]
rb = ring.RingBuilder(8, 3, 1)
next_dev_id = 0
for zone in xrange(1, 10):
for server in xrange(1, 5):
for device in xrange(1, 4):
rb.add_dev({'id': next_dev_id,
'ip': '1.2.%d.%d' % (zone, server),
'port': 1234, 'zone': zone, 'region': 0,
'weight': 1.0})
next_dev_id += 1
rb.rebalance(seed=1)
rb.get_ring().save(self.testgz)
r = ring.Ring(self.testdir, ring_name='whatever')
part, devs = r.get_nodes('a', 'c', 'o')
primary_zones = set([d['zone'] for d in devs])
self.assertEquals(part, exp_part)
self.assertEquals([d['id'] for d in devs], exp_devs)
self.assertEquals(primary_zones, exp_zones)
devs = list(r.get_more_nodes(part))
self.assertEquals([d['id'] for d in devs], exp_handoffs)
# The first 6 replicas plus the 3 primary nodes should cover all 9
# zones in this test
seen_zones = set(primary_zones)
seen_zones.update([d['zone'] for d in devs[:6]])
self.assertEquals(seen_zones, set(range(1, 10)))
# The first handoff nodes for each partition in the ring
devs = []
for part in xrange(r.partition_count):
devs.append(r.get_more_nodes(part).next()['id'])
self.assertEquals(devs, exp_first_handoffs)
# Add a new device we can handoff to.
zone = 5
server = 0
rb.add_dev({'id': next_dev_id,
'ip': '1.2.%d.%d' % (zone, server),
'port': 1234, 'zone': zone, 'region': 0, 'weight': 1.0})
next_dev_id += 1
rb.rebalance(seed=1)
rb.get_ring().save(self.testgz)
r = ring.Ring(self.testdir, ring_name='whatever')
# We would change expectations here, but in this test no handoffs
# changed at all.
part, devs = r.get_nodes('a', 'c', 'o')
primary_zones = set([d['zone'] for d in devs])
self.assertEquals(part, exp_part)
self.assertEquals([d['id'] for d in devs], exp_devs)
self.assertEquals(primary_zones, exp_zones)
devs = list(r.get_more_nodes(part))
dev_ids = [d['id'] for d in devs]
self.assertEquals(len(dev_ids), len(exp_handoffs))
for index, dev in enumerate(dev_ids):
self.assertEquals(
dev, exp_handoffs[index],
'handoff differs at position %d\n%s\n%s' % (
index, dev_ids[index:], exp_handoffs[index:]))
# The handoffs still cover all the non-primary zones first
seen_zones = set(primary_zones)
seen_zones.update([d['zone'] for d in devs[:6]])
self.assertEquals(seen_zones, set(range(1, 10)))
devs = []
for part in xrange(r.partition_count):
devs.append(r.get_more_nodes(part).next()['id'])
for part in xrange(r.partition_count):
self.assertEquals(
devs[part], exp_first_handoffs[part],
'handoff for partitition %d is now device id %d' % (
part, devs[part]))
# Remove a device.
rb.remove_dev(0)
rb.rebalance(seed=1)
rb.get_ring().save(self.testgz)
r = ring.Ring(self.testdir, ring_name='whatever')
# Change expectations
# The long string of handoff nodes for the partition were the same for
# the first 20, which is pretty good.
exp_handoffs[20:] = [60, 108, 8, 72, 56, 19, 91, 13, 84, 38, 66, 52,
1, 78, 107, 50, 57, 31, 32, 77, 24, 42, 100, 71,
26, 9, 20, 35, 5, 14, 94, 28, 41, 18, 102, 101,
61, 95, 21, 81, 105, 58, 74, 90, 86, 46, 4, 68,
40, 80, 54, 75, 45, 79, 44, 49, 62, 29, 7, 15, 70,
87, 65, 12, 82, 17, 104, 97, 55, 22, 6, 89, 2, 67,
37, 63, 53, 92, 33, 85, 73, 51, 98, 36, 10]
# Just a few of the first handoffs changed
exp_first_handoffs[3] = 68
exp_first_handoffs[55] = 104
exp_first_handoffs[116] = 6
exp_first_handoffs[181] = 15
exp_first_handoffs[228] = 38
# Test
part, devs = r.get_nodes('a', 'c', 'o')
primary_zones = set([d['zone'] for d in devs])
self.assertEquals(part, exp_part)
self.assertEquals([d['id'] for d in devs], exp_devs)
self.assertEquals(primary_zones, exp_zones)
devs = list(r.get_more_nodes(part))
dev_ids = [d['id'] for d in devs]
self.assertEquals(len(dev_ids), len(exp_handoffs))
for index, dev in enumerate(dev_ids):
self.assertEquals(
dev, exp_handoffs[index],
'handoff differs at position %d\n%s\n%s' % (
index, dev_ids[index:], exp_handoffs[index:]))
seen_zones = set(primary_zones)
seen_zones.update([d['zone'] for d in devs[:6]])
self.assertEquals(seen_zones, set(range(1, 10)))
devs = []
for part in xrange(r.partition_count):
devs.append(r.get_more_nodes(part).next()['id'])
for part in xrange(r.partition_count):
self.assertEquals(
devs[part], exp_first_handoffs[part],
'handoff for partitition %d is now device id %d' % (
part, devs[part]))
# Add a partial replica
rb.set_replicas(3.5)
rb.rebalance(seed=1)
rb.get_ring().save(self.testgz)
r = ring.Ring(self.testdir, ring_name='whatever')
# Change expectations
# We have another replica now
exp_devs.append(47)
exp_zones.add(4)
# Caused some major changes in the sequence of handoffs for our test
# partition, but at least the first stayed the same.
exp_handoffs[1:] = [81, 25, 69, 23, 99, 59, 76, 3, 106, 64, 43, 13, 34,
88, 30, 16, 27, 103, 39, 74, 60, 108, 8, 56, 19,
91, 52, 84, 38, 66, 1, 78, 45, 107, 50, 57, 83, 31,
46, 32, 77, 24, 42, 63, 100, 72, 71, 7, 26, 9, 20,
35, 5, 87, 14, 94, 62, 28, 41, 90, 18, 82, 102, 22,
101, 61, 85, 95, 21, 98, 67, 105, 58, 86, 4, 79,
68, 40, 80, 54, 75, 44, 49, 6, 29, 15, 70, 65, 12,
17, 104, 97, 55, 89, 2, 37, 53, 92, 33, 73, 51, 36,
10]
# Lots of first handoffs changed, but 30 of 256 is still just 11.72%.
exp_first_handoffs[1] = 6
exp_first_handoffs[4] = 104
exp_first_handoffs[11] = 106
exp_first_handoffs[17] = 13
exp_first_handoffs[21] = 77
exp_first_handoffs[22] = 95
exp_first_handoffs[27] = 46
exp_first_handoffs[29] = 65
exp_first_handoffs[30] = 3
exp_first_handoffs[31] = 20
exp_first_handoffs[51] = 50
exp_first_handoffs[53] = 8
exp_first_handoffs[54] = 2
exp_first_handoffs[72] = 107
exp_first_handoffs[79] = 72
exp_first_handoffs[85] = 71
exp_first_handoffs[88] = 66
exp_first_handoffs[92] = 29
exp_first_handoffs[93] = 46
exp_first_handoffs[96] = 38
exp_first_handoffs[101] = 57
exp_first_handoffs[103] = 87
exp_first_handoffs[104] = 28
exp_first_handoffs[107] = 1
exp_first_handoffs[109] = 69
exp_first_handoffs[110] = 50
exp_first_handoffs[111] = 76
exp_first_handoffs[115] = 47
exp_first_handoffs[117] = 48
exp_first_handoffs[119] = 7
# Test
part, devs = r.get_nodes('a', 'c', 'o')
primary_zones = set([d['zone'] for d in devs])
self.assertEquals(part, exp_part)
self.assertEquals([d['id'] for d in devs], exp_devs)
self.assertEquals(primary_zones, exp_zones)
devs = list(r.get_more_nodes(part))
dev_ids = [d['id'] for d in devs]
self.assertEquals(len(dev_ids), len(exp_handoffs))
for index, dev in enumerate(dev_ids):
self.assertEquals(
dev, exp_handoffs[index],
'handoff differs at position %d\n%s\n%s' % (
index, dev_ids[index:], exp_handoffs[index:]))
seen_zones = set(primary_zones)
seen_zones.update([d['zone'] for d in devs[:6]])
self.assertEquals(seen_zones, set(range(1, 10)))
devs = []
for part in xrange(r.partition_count):
devs.append(r.get_more_nodes(part).next()['id'])
for part in xrange(r.partition_count):
self.assertEquals(
devs[part], exp_first_handoffs[part],
'handoff for partitition %d is now device id %d' % (
part, devs[part]))
# One last test of a partial replica partition
exp_part2 = 136
exp_devs2 = [52, 76, 97]
exp_zones2 = set([9, 5, 7])
exp_handoffs2 = [2, 67, 37, 92, 33, 23, 107, 63, 44, 103, 108, 85,
73, 10, 89, 80, 4, 17, 49, 32, 12, 41, 58, 20, 25,
61, 94, 47, 69, 56, 101, 28, 83, 8, 96, 53, 51, 42,
98, 35, 36, 84, 43, 104, 31, 65, 1, 40, 9, 74, 95,
45, 5, 71, 86, 78, 30, 93, 48, 91, 15, 88, 39, 18,
57, 72, 70, 27, 54, 16, 24, 21, 14, 11, 77, 62, 50,
6, 105, 26, 55, 29, 60, 34, 13, 87, 59, 38, 99, 75,
106, 3, 82, 66, 79, 7, 46, 64, 81, 22, 68, 19, 102,
90, 100]
part2, devs2 = r.get_nodes('a', 'c', 'o2')
primary_zones2 = set([d['zone'] for d in devs2])
self.assertEquals(part2, exp_part2)
self.assertEquals([d['id'] for d in devs2], exp_devs2)
self.assertEquals(primary_zones2, exp_zones2)
devs2 = list(r.get_more_nodes(part2))
dev_ids2 = [d['id'] for d in devs2]
self.assertEquals(len(dev_ids2), len(exp_handoffs2))
for index, dev in enumerate(dev_ids2):
self.assertEquals(
dev, exp_handoffs2[index],
'handoff differs at position %d\n%s\n%s' % (
index, dev_ids2[index:], exp_handoffs2[index:]))
seen_zones = set(primary_zones2)
seen_zones.update([d['zone'] for d in devs2[:6]])
self.assertEquals(seen_zones, set(range(1, 10)))
# Test distribution across regions
rb.set_replicas(3)
for region in xrange(1, 5):
rb.add_dev({'id': next_dev_id,
'ip': '1.%d.1.%d' % (region, server), 'port': 1234,
# 108.0 is the weight of all devices created prior to
# this test in region 0; this way all regions have
# equal combined weight
'zone': 1, 'region': region, 'weight': 108.0})
next_dev_id += 1
rb.pretend_min_part_hours_passed()
rb.rebalance(seed=1)
rb.pretend_min_part_hours_passed()
rb.rebalance(seed=1)
rb.get_ring().save(self.testgz)
r = ring.Ring(self.testdir, ring_name='whatever')
# There's 5 regions now, so the primary nodes + first 2 handoffs
# should span all 5 regions
part, devs = r.get_nodes('a1', 'c1', 'o1')
primary_regions = set([d['region'] for d in devs])
primary_zones = set([(d['region'], d['zone']) for d in devs])
more_devs = list(r.get_more_nodes(part))
seen_regions = set(primary_regions)
seen_regions.update([d['region'] for d in more_devs[:2]])
self.assertEquals(seen_regions, set(range(0, 5)))
# There are 13 zones now, so the first 13 nodes should all have
# distinct zones (that's r0z0, r0z1, ..., r0z8, r1z1, r2z1, r3z1, and
# r4z1).
seen_zones = set(primary_zones)
seen_zones.update([(d['region'], d['zone']) for d in more_devs[:10]])
self.assertEquals(13, len(seen_zones))
# Here's a brittle canary-in-the-coalmine test to make sure the region
# handoff computation didn't change accidentally
exp_handoffs = [111, 112, 74, 54, 93, 31, 2, 43, 100, 22, 71, 92, 35,
9, 50, 41, 76, 80, 84, 88, 17, 96, 6, 102, 37, 29,
105, 5, 47, 20, 13, 108, 66, 81, 53, 65, 25, 58, 32,
94, 101, 1, 10, 44, 73, 75, 21, 97, 28, 106, 30, 16,
39, 77, 42, 72, 34, 99, 14, 61, 90, 4, 40, 3, 45, 62,
7, 15, 87, 12, 83, 89, 33, 98, 49, 107, 56, 86, 48,
57, 24, 11, 23, 26, 46, 64, 69, 38, 36, 79, 63, 104,
51, 70, 82, 67, 68, 8, 95, 91, 55, 59, 85]
dev_ids = [d['id'] for d in more_devs]
self.assertEquals(len(dev_ids), len(exp_handoffs))
for index, dev_id in enumerate(dev_ids):
self.assertEquals(
dev_id, exp_handoffs[index],
'handoff differs at position %d\n%s\n%s' % (
index, dev_ids[index:], exp_handoffs[index:]))
if __name__ == '__main__':
unittest.main()