4 ms·
Has anyone noticed really slow deletes on ZFS? I have a home NAS with RAIDZ and deleting a 1 GB file takes about 30 seconds. I asked on IRC repeatedly but the d
by StavrosK 6y ago
Has anyone noticed really slow deletes on ZFS? I have a home NAS with RAIDZ and deleting a 1 GB file takes about 30 seconds. I asked on IRC repeatedly but the disks just aren't very busy during the delete (or at all) and nobody managed to figure out why this is happening.
It's been that way for years throughout various ZFS versions, and it's driving me crazy.
- mkj 6y agoTry temporarily setting sync=disabled ? If that speeds it maybe a fast ssd log device would fix it.
- StavrosK 6y agoHmm, interesting, I'll try that, thanks!
- ubercow13 6y agoIs it slow if you delete a file locally on the NAS instead of via a network file system?
- StavrosK 6y agoYes, "rm <file>" locally is what's slow :/
- briffle 6y agoZFS deletes can be really slowed down by having dedupe enabled on the pool.
- StavrosK 6y agoIt's off, but I'll triple check, thank you.
- Demiurge 6y agoI have been using Ubuntu + LXD + RaidZ for as long as it was available. Recently (a year ago?) I first had noticed some kind of unclear performance issue with a FLEX container. Heavy file streaming/download would hose and make entire server unusable. I had no idea what to do, and I pretty much randomly converted the LXD storage to BTRFS, and everything was fine. Last few months I ran into same problem with a bunch of PostgreSQL containers doings lots of writes, and same solution helped. Not sure if it's a ZFS problem or LXD, but I will not use ZFS in high load scenario again.
- craigyk 6y agoI think deletes in ZFS are just slow, my guess is it is doing work to update/coalesce free segments lists so that future writes stay fast.