openstack/cinder
Code Issues Proposed changes

Non Windows per service lock for Backup service

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The introduction of multiple processes on the Backup service in commit
66b1a0049a broke the service in Windows.

On commit 1710839a43 this was fixed by
removing the original usage of os.getpgrp and using a global lock for
all backup services running on the host.

This global lock introduces an unnecessary bottleneck on non Windows
systems.

This patch fixes this bottleneck on non Windows systems by going back to
using a lock using the os.getpgrp method for non Windows systems and
using a global lock for Windows systems.

Related-Bug: #1781168
Change-Id: If7178695bf8ab751bcede14aa56d8becee60e17b
This commit is contained in:
Gorka Eguileor 2018-07-19 10:32:22 +02:00
parent 49507ea1c0
commit 6cfe4fb364
1 changed files with 5 additions and 2 deletions
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7
cinder/backup/manager.py
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@ -96,6 +96,7 @@ MAPPING = {
# driver when it imports google.auth
'cinder.backup.drivers.google': 'cinder.backup.drivers.gcs',
}
SERVICE_PGRP = '' if os.name == 'nt' else os.getpgrp()
# TODO(geguileo): Once Eventlet issue #432 gets fixed we can just tpool.execute
@ -190,14 +191,16 @@ class BackupManager(manager.ThreadPoolManager):
self.backup_rpcapi = backup_rpcapi.BackupAPI()
self.volume_rpcapi = volume_rpcapi.VolumeAPI()
@utils.synchronized('cleanup_incomplete_backups',
@utils.synchronized('cleanup_incomplete_backups_%s' % SERVICE_PGRP,
external=True, delay=0.1)
def _cleanup_incomplete_backup_operations(self, ctxt):
# Only the first launched process should do the cleanup, the others
# have waited on the lock for the first one to finish the cleanup and
# can now continue with the start process.
if self._process_number != 1:
LOG.debug("Process #%s skips cleanup.", self._process_number)
LOG.debug("Process #%s %sskips cleanup.",
self._process_number,
'(pgid=%s) ' % SERVICE_PGRP if SERVICE_PGRP else '')
return
LOG.info("Cleaning up incomplete backup operations.")