[Bug 223950] lower default kern.cam.da.X.delete_max to avoid ZFS TRIM timeouts

bugzilla-noreply at freebsd.org bugzilla-noreply at freebsd.org
Tue Nov 28 22:38:07 UTC 2017


https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=223950

            Bug ID: 223950
           Summary: lower default kern.cam.da.X.delete_max to avoid ZFS
                    TRIM timeouts
           Product: Base System
           Version: 11.1-RELEASE
          Hardware: amd64
                OS: Any
            Status: New
          Severity: Affects Some People
          Priority: ---
         Component: kern
          Assignee: freebsd-bugs at FreeBSD.org
          Reporter: jim at ks.uiuc.edu

We are seeing the issue with ZFS described at
https://lists.freebsd.org/pipermail/freebsd-scsi/2015-July/006777.html
where SATA SSDs on a SAS controller will time out on TRIM commands.

This was the original state, with TRIM failures recorded in kstat:

kern.geom.dev.delete_max_sectors: 262144
kern.cam.da.4.delete_max: 17179607040
kern.cam.da.4.delete_method: ATA_TRIM
kern.cam.da.3.delete_max: 17179607040
kern.cam.da.3.delete_method: ATA_TRIM
kern.cam.da.2.delete_max: 17179607040
kern.cam.da.2.delete_method: ATA_TRIM
kern.cam.da.5.delete_max: 17179607040
kern.cam.da.5.delete_method: ATA_TRIM
kern.cam.da.1.delete_max: 17179607040
kern.cam.da.1.delete_method: ATA_TRIM
kern.cam.da.0.delete_max: 17179607040
kern.cam.da.0.delete_method: ATA_TRIM
kern.cam.ada.0.delete_method: DSM_TRIM
vfs.zfs.trim.max_interval: 1
vfs.zfs.trim.timeout: 30
vfs.zfs.trim.txg_delay: 32
vfs.zfs.trim.enabled: 1
vfs.zfs.vdev.trim_max_pending: 10000
vfs.zfs.vdev.bio_delete_disable: 0
vfs.zfs.vdev.trim_max_active: 64
vfs.zfs.vdev.trim_min_active: 1
vfs.zfs.vdev.trim_on_init: 1
hw.nvd.delete_max: 1073741824
kstat.zfs.misc.arcstats.deleted: 138850
kstat.zfs.misc.zio_trim.failed: 9399097
kstat.zfs.misc.zio_trim.unsupported: 0
kstat.zfs.misc.zio_trim.success: 792148930
kstat.zfs.misc.zio_trim.bytes: 31513520795648

Our current workaround is to lower delete_max (for all drives):
sysctl kern.cam.da.0.delete_max=536870912

I suggest a lower default value than the current 17179607040.

-- 
You are receiving this mail because:
You are the assignee for the bug.


More information about the freebsd-bugs mailing list