du shows less amount of used space on Virtuozzo Storage than
# df -h | grep pstorage\/pcs pstorage://pcs 7.1T 566G 6.6T 8% /pstorage/pcs # du -sh /pstorage/pcs/ 201G /pstorage/pcs/
pstorage stat also shows difference between the amount of total/allocatable space and used capacity of the license:
# pstorage -c pcs stat | head ... Space: [OK] allocatable 6.52TB of 7.08TB, free 20.6TB of 21.2TB ... License: ACTIVE (expiration: 08/19/2015, capacity: 6399.9TB, used: 200.8GB) Replication: 3 norm, 2 limit ...
By default, Virtuozzo Storage reserves 5% of available space for emergency cases. So this space cannot be allocated. In the example above:
7.08 TB * 0.05 = 0.354 TB
7.08 - 6.52 = 0.56 TB
0.56 TB - 0,354 TB = 0.216 TB
which is approximately 200 GB of actual used space.
In case of critical necessity, it is possible to decrease the amount of reserved space. It is highly recommnended to perform this action only in case of utmost urgency:
# pstorage -c pcs set-config mds.alloc.fill_margin=2
The command above decreasese the reservation level from 5% to 2%.