Public bug reported:
wait for coalesce scans the SR then checks if the GC has finished.
The GC might finish between the two calls, so the state of the system is pre-GC
but the GC claims not to be running.
This is a race which can cause an error when actually the state is now
correct.
The order of the scan / GC check must be switched.
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/compute/manager.py", line 2455, in backup_instance
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
task_states.IMAGE_BACKUP)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/compute/manager.py", line 2521, in _snapshot_instance
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
update_task_state)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/driver.py", line 261, in snapshot
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
self._vmops.snapshot(context, instance, image_id, update_task_state)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vmops.py", line 750, in snapshot
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
post_snapshot_callback=update_task_state) as vdi_uuids:
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/usr/lib/python2.7/contextlib.py", line 17, in __enter__
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher return
self.gen.next()
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vm_utils.py", line 790, in
_snapshot_attached_here_impl
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
original_parent_uuid)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vm_utils.py", line 2114, in
_wait_for_vhd_coalesce
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher raise
exception.NovaException(msg)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher NovaException: VHD
coalesce: Garbage collection not running, giving up...
** Affects: nova
Importance: Critical
Assignee: Bob Ball (bob-ball)
Status: New
** Tags: xenserver
--
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to OpenStack Compute (nova).
https://bugs.launchpad.net/bugs/1282822
Title:
XenAPI: Race condition in wait for coalesce
Status in OpenStack Compute (Nova):
New
Bug description:
wait for coalesce scans the SR then checks if the GC has finished.
The GC might finish between the two calls, so the state of the system is
pre-GC but the GC claims not to be running.
This is a race which can cause an error when actually the state is now
correct.
The order of the scan / GC check must be switched.
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/compute/manager.py", line 2455, in backup_instance
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
task_states.IMAGE_BACKUP)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/compute/manager.py", line 2521, in _snapshot_instance
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
update_task_state)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/driver.py", line 261, in snapshot
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
self._vmops.snapshot(context, instance, image_id, update_task_state)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vmops.py", line 750, in snapshot
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
post_snapshot_callback=update_task_state) as vdi_uuids:
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/usr/lib/python2.7/contextlib.py", line 17, in __enter__
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher return
self.gen.next()
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vm_utils.py", line 790, in
_snapshot_attached_here_impl
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher
original_parent_uuid)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher File
"/opt/stack/nova/nova/virt/xenapi/vm_utils.py", line 2114, in
_wait_for_vhd_coalesce
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher raise
exception.NovaException(msg)
2014-02-20 20:26:55.336 TRACE oslo.messaging.rpc.dispatcher NovaException:
VHD coalesce: Garbage collection not running, giving up...
To manage notifications about this bug go to:
https://bugs.launchpad.net/nova/+bug/1282822/+subscriptions
--
Mailing list: https://launchpad.net/~yahoo-eng-team
Post to : yahoo-eng-team@lists.launchpad.net
Unsubscribe : https://launchpad.net/~yahoo-eng-team
More help : https://help.launchpad.net/ListHelp
