A.3. Synchronizing Quotas with the gfs2_quota Command

GFS2 stores all quota information in its own internal file on disk. A GFS2 node does not update this quota file for every file system write; rather, by default it updates the quota file once every 60 seconds. This is necessary to avoid contention among nodes writing to the quota file, which would cause a slowdown in performance.

As a user or group approaches their quota limit, GFS2 dynamically reduces the time between its quota-file updates to prevent the limit from being exceeded. The normal time period between quota synchronizations is a tunable parameter, quota_quantum. You can change this from its default value of 60 seconds using the quota_quantum= mount option, as described in Table 4.2, “GFS2-Specific Mount Options”. The quota_quantum parameter must be set on each node and each time the file system is mounted. Changes to the quota_quantum parameter are not persistent across unmounts. You can update the quota_quantum value with the mount -o remount.

You can use the gfs2_quota sync command to synchronize the quota information from a node to the on-disk quota file between the automatic updates performed by GFS2.

gfs2_quota sync -f MountPoint

mount -o quota_quantum=secs,remount BlockDevice MountPoint

# gfs2_quota sync -f /mygfs2

# mount -o quota_quantum=3600,remount /dev/volgroup/logical_volume /mnt/mygfs2