mirror of
https://git.proxmox.com/git/mirror_zfs.git
synced 2024-12-26 03:09:34 +03:00
30930fba21
DISCARD (REQ_DISCARD, BLKDISCARD) is useful for thin provisioning. It allows ZVOL clients to discard (unmap, trim) block ranges from a ZVOL, thus optimizing disk space usage by allowing a ZVOL to shrink instead of just grow. We can't use zfs_space() or zfs_freesp() here, since these functions only work on regular files, not volumes. Fortunately we can use the low-level function dmu_free_long_range() which does exactly what we want. Currently the discard operation is not added to the log. That's not a big deal since losing discard requests cannot result in data corruption. It would however result in disk space usage higher than it should be. Thus adding log support to zvol_discard() is probably a good idea for a future improvement. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> |
||
---|---|---|
.. | ||
1th-16rc-4rs-1cs-4off.sh | ||
1x256th-65536rc-4rs-1cs-4off.sh | ||
4th-1024rc-4rs-1cs-4off.sh | ||
16th-8192rc-4rs-1cs-4off.sh | ||
256th-65536rc-4rs-1cs-4off.sh | ||
large-thread-survey.sh | ||
large.sh | ||
lustre.sh | ||
Makefile.am | ||
Makefile.in | ||
medium.sh | ||
small.sh | ||
tiny.sh |