Resilver performance on TrueNAS 12.x - tunable vfs.zfs.resilver_delay missing?

[goelli]

Hi all,

Longterm reader, now first poster. Most time it is difficult to have a problem, which nobody has solved already

I have TrueNAS-12.0-U7 with a Pool of 2 RaidZ2 vdevs with 6 HDD each. Now I started exchanging the disks of one vdev one-by-one with new discs with more capacity. The replacing is working fine and the resilvering speed is great, but it is using about 70% CPU (2x Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz). This is impacting transcoding performance of Plex Plugin, so I started searching about what is tunable in scrubbing or resilvering.

• Scrubbing can be paused, but resilvering not.
• Resilvering can be made higher priority (see this thread), but not lower.
• Tunables are described here, but sysctl says: unknown oid 'vfs.zfs.resilver_delay'

Are these tunables, especially vfs.zfs.resilver_delay still available in TrueNAS 12.0 or was there any change? If yes: How can I adjust them (maybe I'm just doing it wrong...)? If no: Is there any other possibility to make the resilvering more nice?

I understand the consideration, that resilvering has to be as fast as possible, but in my case this is not true. As I have RaidZ2 and replace the healthy disks one-by-one, I can tolerate the risk of one disk failing. So in my case the resilvering should consume less CPU and less IOPS to have as least impact on normal operation of the system as possible.

Any input is appreciated

Best regards,
Gölli

 

[goelli]

Sorry, I've overseen xmrig running *dumb*
But I think the question is still valid. Xmrig and Plex Transcoding in parallel is no problem without resilvering.