Even with the sysctl "vfs.zfs.scrub_limit" given value 2, scrubbing my 8-disk array is an exercise in frustration. The system remains online, and will eventually respond to events, but it's incredibly lagged, even when the events do not directly relate to the controller card and disks making up the array. The array is 4x320G and 4x750G SATA disks on a mpt0: <LSILogic SAS/SATA Adapter> port 0x300-0x3ff mem 0x100000-0x103fff,0x130000-0x13ffff at device 1.0 on pci3 mpt0: MPI Version=1.5.10.0 For (I assume unrelated) stability reasons (see pr kern/117688), I have had to run "camcontrol tags $DISK -N 16" for each of the disks in the array. WITNESS and INVARIANTS are both turned on; I've not tried with them off; should I? How-To-Repeat: Reliably triggered by issuing a scrub request.
Responsible Changed From-To: freebsd-bugs->freebsd-fs Over to maintainer(s).
State Changed From-To: open->feedback Could you tell which threads are consuming most CPU time? Pasting first few lines from 'top -SH' should be enough.
Responsible Changed From-To: freebsd-fs->pjd I'll take this one.
State Changed From-To: feedback->suspended I cannot reproduce the problem on my test machine, it can be related to the mpt(4) driver and not ZFS, hard to say. Suspend PR for now.
batch change: For bugs that match the following - Status Is In progress AND - Untouched since 2018-01-01. AND - Affects Base System OR Documentation DO: Reset to open status. Note: I did a quick pass but if you are getting this email it might be worthwhile to double check to see if this bug ought to be closed.
^Triage: I'm sorry that this PR did not get addressed in a timely fashion. By now, the version that it was created against is long out of support. As well, many newer versions of ZFS have been imported. Please re-open if it is still a problem on a supported version.