Hello.
I use zfs to create zvols. This is the zpool list:
NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
zfspool 14.5T 10.7T 3.75T - 13% 74% 1.00x ONLINE -
I have 3.75T free to create more zvols or extend existing vols.
I have several zvols created as blockdevices, zfs list -o space:
NAME AVAIL USED USEDSNAP USEDDS USEDREFRESERV USEDCHILD
zfspool 0 11.5T 0 335K 0 11.5T
zfspool/1 57.4G 103G 0 45.8G 57.4G 0
zfspool/2 120G 4.13T 0 4.01T 120G 0
zfspool/3 50.3G 103G 0 52.9G 50.3G 0
zfspool/4 51.1G 51.6G 0 445M 51.1G 0
zfspool/5 1008G 1.03T 0 48.6G 1008G 0
zfspool/6 353G 413G 0 59.4G 353G 0
zfspool/7 1.03T 1.03T 0 45.1M 1.03T 0
zfspool/8 75.4G 103G 0 27.7G 75.4G 0
zfspool/9 0 4.58T 0 4.58T 0 0
As you can see, zfspool hase no free space available. This volume was
created with this:
zfs create -V 4T zfspool/9
zfs set compression=lz4 zfspool/9
mkfs.ext4 -b 4096 -q /dev/zvol/zfspool/9
mkdir -p /mnt/zfs/9
mount /dev/zvol/zfspool/9 /mnt/zfs/9
The problem is that while zfs list reports 0 free space, actual data
ocupies only about a half of the space (~1.5TB). Also df -h /mnt/zfs/9:
Filesystem Size Used Avail Use% Mounted on
/dev/zd48 4.0T 1.6T 2.3T 41% /mnt/zfs/oracle
Which is correct.
I don't use deduplication or snapshots.
This is the output of zfs get all zfspool/9
NAME PROPERTY VALUE SOURCE
zfspool/oracle type volume -
zfspool/oracle creation Thu Mar 26 9:33 2015 -
zfspool/oracle used 4.58T -
zfspool/oracle available 0 -
zfspool/oracle referenced 4.58T -
zfspool/oracle compressratio 1.00x -
zfspool/oracle reservation none default
zfspool/oracle volsize 4T local
zfspool/oracle volblocksize 8K -
zfspool/oracle checksum on default
zfspool/oracle compression lz4 local
zfspool/oracle readonly off default
zfspool/oracle copies 1 default
zfspool/oracle refreservation 4.13T local
zfspool/oracle primarycache all default
zfspool/oracle secondarycache all default
zfspool/oracle usedbysnapshots 0 -
zfspool/oracle usedbydataset 4.58T -
zfspool/oracle usedbychildren 0 -
zfspool/oracle usedbyrefreservation 0 -
zfspool/oracle logbias latency default
zfspool/oracle dedup off inherited
from zfspool
zfspool/oracle mlslabel none default
zfspool/oracle sync standard default
zfspool/oracle refcompressratio 1.00x -
zfspool/oracle written 4.58T -
zfspool/oracle logicalused 1.85T -
zfspool/oracle logicalreferenced 1.85T -
zfspool/oracle snapshot_limit none default
zfspool/oracle snapshot_count none default
zfspool/oracle snapdev hidden default
zfspool/oracle context none default
zfspool/oracle fscontext none default
zfspool/oracle defcontext none default
zfspool/oracle rootcontext none default
zfspool/oracle redundant_metadata all default
zfspool/oracle shareiscsi off default
Here logicalused display 1.85TB of data. Why rest of the space is not
available?
Thank you.
