c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-05-24 11:18:52 +03:00
Code Issues Packages Projects Releases Wiki Activity

Improve allocation fallback handling

Browse Source 
Before this change in case of any allocation error ZFS always fallen
back to normal class.  But with more of different classes available
we migth want more sophisticated logic.  For example, it makes sense
to fall back from dedup first to special class (if it is allowed to
put DDT there) and only then to normal, since in a pool with dedup
and special classes populated normal class likely has performance
characteristics unsuitable for dedup.

This change implements general mechanism where fallback order is
controlled by the same spa_preferred_class() as the initial class
selection.  And as first application it implements the mentioned
dedup->special->normal fallbacks.  I have more plans for it later.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #17391
This commit is contained in:
Alexander Motin
2025-05-31 19:12:16 -04:00
committed by GitHub
parent e0edfcbd4e
commit 108562344c
4 changed files with 74 additions and 61 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/sys/spa.h
+2
View File
@@ -1116,7 +1116,9 @@ extern boolean_t spa_has_spare(spa_t *, uint64_t guid);
extern uint64_t dva_get_dsize_sync(spa_t *spa, const dva_t *dva);
extern uint64_t bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp);
extern uint64_t bp_get_dsize(spa_t *spa, const blkptr_t *bp);
extern boolean_t spa_has_dedup(spa_t *spa);
extern boolean_t spa_has_slogs(spa_t *spa);
extern boolean_t spa_has_special(spa_t *spa);
extern boolean_t spa_is_root(spa_t *spa);
extern boolean_t spa_writeable(spa_t *spa);
extern boolean_t spa_has_pending_synctask(spa_t *spa);