swift/test/unit/cli/test_relinker.py
Romain LE DISEZ 3061ec803f relinker: Improve performance by limiting I/O
This commit reduce the number of I/O done by the swift-object-relinker.

First, it saves a progress state of relinking and cleanup in case the
process is interrupted during the operation. This allow to resume
operation without rescanning all partitions.

Secondly, it prevents from being scanned by relink and cleanup all
partitions that are bigger than 2^part_power (or (2^next_part_power)/2).
These partitions were not existing before the beginning of the part_power
increase, so there is nothing to relink or cleanup.

Thirdly, it reverse-orders the partitions to scan so that some useless
work is avoided. If a device contains partitions 1 and 3, relinking
partition 1 will create "new" objects in partition 3, that will need to
be scanned when the relinker will work on partition 3. It is useless. If
partition 3 is done first, it will only contain the objects that need to
be relinked.

Fourthly, it allows to specify a unique device to work on.

To do that, some hooks were added in audit_location_generator to allow
to execute some custom code before/after iterating a
device/partition/suffix/hash.

Change-Id: If1bf8ed9036fb0ec619b0d4f16061a81a1af2082
2020-03-31 17:33:06 -04:00

391 lines
16 KiB
Python

# 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 binascii
import errno
import fcntl
import json
import os
import shutil
import struct
import tempfile
import unittest
from swift.cli import relinker
from swift.common import exceptions, ring, utils
from swift.common import storage_policy
from swift.common.storage_policy import (
StoragePolicy, StoragePolicyCollection, POLICIES, ECStoragePolicy)
from swift.obj.diskfile import write_metadata
from test.unit import FakeLogger, skip_if_no_xattrs, DEFAULT_TEST_EC_TYPE, \
patch_policies
PART_POWER = 8
class TestRelinker(unittest.TestCase):
def setUp(self):
skip_if_no_xattrs()
self.logger = FakeLogger()
self.testdir = tempfile.mkdtemp()
self.devices = os.path.join(self.testdir, 'node')
shutil.rmtree(self.testdir, ignore_errors=1)
os.mkdir(self.testdir)
os.mkdir(self.devices)
self.rb = ring.RingBuilder(PART_POWER, 6.0, 1)
for i in range(6):
ip = "127.0.0.%s" % i
self.rb.add_dev({'id': i, 'region': 0, 'zone': 0, 'weight': 1,
'ip': ip, 'port': 10000, 'device': 'sda1'})
self.rb.rebalance(seed=1)
self.existing_device = 'sda1'
os.mkdir(os.path.join(self.devices, self.existing_device))
self.objects = os.path.join(self.devices, self.existing_device,
'objects')
os.mkdir(self.objects)
self._hash = utils.hash_path('a/c/o')
digest = binascii.unhexlify(self._hash)
self.part = struct.unpack_from('>I', digest)[0] >> 24
self.next_part = struct.unpack_from('>I', digest)[0] >> 23
self.objdir = os.path.join(
self.objects, str(self.part), self._hash[-3:], self._hash)
os.makedirs(self.objdir)
self.object_fname = "1278553064.00000.data"
self.objname = os.path.join(self.objdir, self.object_fname)
with open(self.objname, "wb") as dummy:
dummy.write(b"Hello World!")
write_metadata(dummy, {'name': '/a/c/o', 'Content-Length': '12'})
test_policies = [StoragePolicy(0, 'platin', True)]
storage_policy._POLICIES = StoragePolicyCollection(test_policies)
self.expected_dir = os.path.join(
self.objects, str(self.next_part), self._hash[-3:], self._hash)
self.expected_file = os.path.join(self.expected_dir, self.object_fname)
def _save_ring(self):
rd = self.rb.get_ring()
for policy in POLICIES:
rd.save(os.path.join(
self.testdir, '%s.ring.gz' % policy.ring_name))
# Enforce ring reloading in relinker
policy.object_ring = None
def tearDown(self):
shutil.rmtree(self.testdir, ignore_errors=1)
storage_policy.reload_storage_policies()
def test_relink(self):
self.rb.prepare_increase_partition_power()
self._save_ring()
relinker.relink(self.testdir, self.devices, True)
self.assertTrue(os.path.isdir(self.expected_dir))
self.assertTrue(os.path.isfile(self.expected_file))
stat_old = os.stat(os.path.join(self.objdir, self.object_fname))
stat_new = os.stat(self.expected_file)
self.assertEqual(stat_old.st_ino, stat_new.st_ino)
def test_relink_device_filter(self):
self.rb.prepare_increase_partition_power()
self._save_ring()
relinker.relink(self.testdir, self.devices, True,
device=self.existing_device)
self.assertTrue(os.path.isdir(self.expected_dir))
self.assertTrue(os.path.isfile(self.expected_file))
stat_old = os.stat(os.path.join(self.objdir, self.object_fname))
stat_new = os.stat(self.expected_file)
self.assertEqual(stat_old.st_ino, stat_new.st_ino)
def test_relink_device_filter_invalid(self):
self.rb.prepare_increase_partition_power()
self._save_ring()
relinker.relink(self.testdir, self.devices, True, device='none')
self.assertFalse(os.path.isdir(self.expected_dir))
self.assertFalse(os.path.isfile(self.expected_file))
def _common_test_cleanup(self, relink=True):
# Create a ring that has prev_part_power set
self.rb.prepare_increase_partition_power()
self.rb.increase_partition_power()
self._save_ring()
os.makedirs(self.expected_dir)
if relink:
# Create a hardlink to the original object name. This is expected
# after a normal relinker run
os.link(os.path.join(self.objdir, self.object_fname),
self.expected_file)
def test_cleanup(self):
self._common_test_cleanup()
self.assertEqual(0, relinker.cleanup(self.testdir, self.devices, True))
# Old objectname should be removed, new should still exist
self.assertTrue(os.path.isdir(self.expected_dir))
self.assertTrue(os.path.isfile(self.expected_file))
self.assertFalse(os.path.isfile(
os.path.join(self.objdir, self.object_fname)))
def test_cleanup_device_filter(self):
self._common_test_cleanup()
self.assertEqual(0, relinker.cleanup(self.testdir, self.devices, True,
device=self.existing_device))
# Old objectname should be removed, new should still exist
self.assertTrue(os.path.isdir(self.expected_dir))
self.assertTrue(os.path.isfile(self.expected_file))
self.assertFalse(os.path.isfile(
os.path.join(self.objdir, self.object_fname)))
def test_cleanup_device_filter_invalid(self):
self._common_test_cleanup()
self.assertEqual(0, relinker.cleanup(self.testdir, self.devices, True,
device='none'))
# Old objectname should still exist, new should still exist
self.assertTrue(os.path.isdir(self.expected_dir))
self.assertTrue(os.path.isfile(self.expected_file))
self.assertTrue(os.path.isfile(
os.path.join(self.objdir, self.object_fname)))
def test_relink_cleanup(self):
state_file = os.path.join(self.devices, self.existing_device,
'relink.objects.json')
self.rb.prepare_increase_partition_power()
self._save_ring()
relinker.relink(self.testdir, self.devices, True)
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f), {str(self.part): [True, False]})
self.rb.increase_partition_power()
self.rb._ring = None # Force builder to reload ring
self._save_ring()
relinker.cleanup(self.testdir, self.devices, True)
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f),
{str(self.part): [True, True],
str(self.next_part): [True, True]})
def test_devices_filter_filtering(self):
# With no filtering, returns all devices
devices = relinker.devices_filter(None, "", [self.existing_device])
self.assertEqual(set([self.existing_device]), devices)
# With a matching filter, returns what is matching
devices = relinker.devices_filter(self.existing_device, "",
[self.existing_device, 'sda2'])
self.assertEqual(set([self.existing_device]), devices)
# With a non matching filter, returns nothing
devices = relinker.devices_filter('none', "", [self.existing_device])
self.assertEqual(set(), devices)
def test_hook_pre_post_device_locking(self):
locks = [None]
device_path = os.path.join(self.devices, self.existing_device)
datadir = 'object'
lock_file = os.path.join(device_path, '.relink.%s.lock' % datadir)
# The first run gets the lock
relinker.hook_pre_device(locks, {}, datadir, device_path)
self.assertNotEqual([None], locks)
# A following run would block
with self.assertRaises(IOError) as raised:
with open(lock_file, 'a') as f:
fcntl.flock(f.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
self.assertEqual(errno.EAGAIN, raised.exception.errno)
# Another must not get the lock, so it must return an empty list
relinker.hook_post_device(locks, "")
self.assertEqual([None], locks)
with open(lock_file, 'a') as f:
fcntl.flock(f.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
def test_state_file(self):
device_path = os.path.join(self.devices, self.existing_device)
datadir = 'objects'
datadir_path = os.path.join(device_path, datadir)
state_file = os.path.join(device_path, 'relink.%s.json' % datadir)
def call_partition_filter(step, parts):
# Partition 312 will be ignored because it must have been created
# by the relinker
return relinker.partitions_filter(states, step,
PART_POWER, PART_POWER + 1,
datadir_path, parts)
# Start relinking
states = {}
# Load the states: As it starts, it must be empty
locks = [None]
relinker.hook_pre_device(locks, states, datadir, device_path)
self.assertEqual({}, states)
os.close(locks[0]) # Release the lock
# Partition 312 is ignored because it must have been created with the
# next_part_power, so it does not need to be relinked
# 96 and 227 are reverse ordered
# auditor_status_ALL.json is ignored because it's not a partition
self.assertEqual(['227', '96'],
call_partition_filter(relinker.STEP_RELINK,
['96', '227', '312',
'auditor_status.json']))
self.assertEqual(states, {'96': [False, False], '227': [False, False]})
# Ack partition 96
relinker.hook_post_partition(states, relinker.STEP_RELINK,
os.path.join(datadir_path, '96'))
self.assertEqual(states, {'96': [True, False], '227': [False, False]})
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f), {'96': [True, False],
'227': [False, False]})
# Restart relinking after only part 96 was done
self.assertEqual(['227'],
call_partition_filter(relinker.STEP_RELINK,
['96', '227', '312']))
self.assertEqual(states, {'96': [True, False], '227': [False, False]})
# Ack partition 227
relinker.hook_post_partition(states, relinker.STEP_RELINK,
os.path.join(datadir_path, '227'))
self.assertEqual(states, {'96': [True, False], '227': [True, False]})
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f), {'96': [True, False],
'227': [True, False]})
# If the process restarts, it reload the state
locks = [None]
states = {}
relinker.hook_pre_device(locks, states, datadir, device_path)
self.assertEqual(states, {'96': [True, False], '227': [True, False]})
os.close(locks[0]) # Release the lock
# Start cleanup
self.assertEqual(['227', '96'],
call_partition_filter(relinker.STEP_CLEANUP,
['96', '227', '312']))
# Ack partition 227
relinker.hook_post_partition(states, relinker.STEP_CLEANUP,
os.path.join(datadir_path, '227'))
self.assertEqual(states, {'96': [True, False], '227': [True, True]})
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f), {'96': [True, False],
'227': [True, True]})
# Restart cleanup after only part 227 was done
self.assertEqual(['96'],
call_partition_filter(relinker.STEP_CLEANUP,
['96', '227', '312']))
self.assertEqual(states, {'96': [True, False], '227': [True, True]})
# Ack partition 96
relinker.hook_post_partition(states, relinker.STEP_CLEANUP,
os.path.join(datadir_path, '96'))
self.assertEqual(states, {'96': [True, True], '227': [True, True]})
with open(state_file, 'rt') as f:
self.assertEqual(json.load(f), {'96': [True, True],
'227': [True, True]})
# At the end, the state is still accurate
locks = [None]
states = {}
relinker.hook_pre_device(locks, states, datadir, device_path)
self.assertEqual(states, {'96': [True, True], '227': [True, True]})
os.close(locks[0]) # Release the lock
# If the file gets corrupted, restart from scratch
with open(state_file, 'wt') as f:
f.write('NOT JSON')
locks = [None]
states = {}
relinker.hook_pre_device(locks, states, datadir, device_path)
self.assertEqual(states, {})
os.close(locks[0]) # Release the lock
def test_cleanup_not_yet_relinked(self):
self._common_test_cleanup(relink=False)
self.assertEqual(1, relinker.cleanup(self.testdir, self.devices, True))
self.assertTrue(os.path.isfile(
os.path.join(self.objdir, self.object_fname)))
def test_cleanup_deleted(self):
self._common_test_cleanup()
# Pretend the object got deleted inbetween and there is a tombstone
fname_ts = self.expected_file[:-4] + "ts"
os.rename(self.expected_file, fname_ts)
self.assertEqual(0, relinker.cleanup(self.testdir, self.devices, True))
def test_cleanup_doesnotexist(self):
self._common_test_cleanup()
# Pretend the file in the new place got deleted inbetween
os.remove(self.expected_file)
self.assertEqual(
1, relinker.cleanup(self.testdir, self.devices, True, self.logger))
self.assertEqual(self.logger.get_lines_for_level('warning'),
['Error cleaning up %s: %s' % (self.objname,
repr(exceptions.DiskFileNotExist()))])
@patch_policies(
[ECStoragePolicy(
0, name='platin', is_default=True, ec_type=DEFAULT_TEST_EC_TYPE,
ec_ndata=4, ec_nparity=2)])
def test_cleanup_non_durable_fragment(self):
self._common_test_cleanup()
# Switch the policy type so that actually all fragments are non-durable
# and raise a DiskFileNotExist in EC in this test. However, if the
# counterpart exists in the new location, this is ok - it will be fixed
# by the reconstructor later on
self.assertEqual(
0, relinker.cleanup(self.testdir, self.devices, True,
self.logger))
self.assertEqual(self.logger.get_lines_for_level('warning'), [])
def test_cleanup_quarantined(self):
self._common_test_cleanup()
# Pretend the object in the new place got corrupted
with open(self.expected_file, "wb") as obj:
obj.write(b'trash')
self.assertEqual(
1, relinker.cleanup(self.testdir, self.devices, True, self.logger))
self.assertIn('failed audit and was quarantined',
self.logger.get_lines_for_level('warning')[0])
if __name__ == '__main__':
unittest.main()