vxevac triggers an immediate thin reclaimation
Article ID: 100032846
Updated On:
Cause
This behavior is by design. When vxevac is run, the following commands are logged in the VxVM (Volume Manager) command log (normally found here: /var/adm/vx/cmdlog). Since vxevac is a shell script, the execution of vxevac is not logged in the command log. vxevac will use vxassist to perform the migration of the volume data away from the specified disk.
vxassist will then run vxsd -o rm mv to move the data from the original subdisk, to a new subdisk.
When vxsd finishes moving the data, it will instruct vxconfigd to post events. vxrelocd is the daemon listening to the posted events. It performs the actual thin reclamation, if required. In particular, the following two events will cause vxrelocd to immediately perform the thin reclamation.
The Storage-Reclaim message will cause vxrelocd to store the subdisk oldsubdisk-01 in the pending list of subdisks to be reclaimed. The second message, changed subdisk, will cause vxrelocd to perform the thin reclamation immediately, by running the following command:
# 57499364, 664, Wed Jul 27 15:46:05 2016
/usr/sbin/vxassist -g mydg move myvol !diskA -t tagX
/usr/sbin/vxassist -g mydg move myvol !diskA -t tagX
vxassist will then run vxsd -o rm mv to move the data from the original subdisk, to a new subdisk.
# 1145242731, 672, Wed Jul 27 15:46:05 2016
/etc/vx/type/fsgen/vxsd -U fsgen -g 1234567890.167.hostA -t tagX -o rm -- mv oldsubdisk-01 newsubdisk-01
/etc/vx/type/fsgen/vxsd -U fsgen -g 1234567890.167.hostA -t tagX -o rm -- mv oldsubdisk-01 newsubdisk-01
When vxsd finishes moving the data, it will instruct vxconfigd to post events. vxrelocd is the daemon listening to the posted events. It performs the actual thin reclamation, if required. In particular, the following two events will cause vxrelocd to immediately perform the thin reclamation.
Messages sent to vxrelocd:
Storage-Reclaim pending subdisk oldsubdisk-01 dg mydg
changed subdisk newsubdisk-01 (was -) in dg mydg
Storage-Reclaim pending subdisk oldsubdisk-01 dg mydg
changed subdisk newsubdisk-01 (was -) in dg mydg
The Storage-Reclaim message will cause vxrelocd to store the subdisk oldsubdisk-01 in the pending list of subdisks to be reclaimed. The second message, changed subdisk, will cause vxrelocd to perform the thin reclamation immediately, by running the following command:
# 168082833, 22411, Wed Jul 27 15:46:35 2016
/usr/sbin/vxdisk -g my -o subdisk reclaim all
/usr/sbin/vxdisk -g my -o subdisk reclaim all
Resolution
The immediate thin reclamation, by vxevac, is by design.
Issue/Introduction
The vxevac command triggers an immediate thin reclaimation operation, regardless of the reclaim_on_delete_wait_period setting.
Was this article helpful?
Yes
No
Powered by
