Possible deadlock with nfsd

[William Jagels]

Missed one part,

I also apply these tunables after boot:
sysctl vfs.zfs.top_maxinflight=128
sysctl vfs.zfs.delay_min_dirty_percent=96
sysctl vfs.zfs.vdev.write_gap_limit=16384
sysctl vfs.zfs.dirty_data_sync=12348030976
sysctl vfs.zfs.dirty_data_max=12884901888

On Sun, Mar 3, 2019 at 6:53 PM William Jagels <william at jagels.us> wrote:

> Hi,
>
> I've been running into something (4 or so occurrences) that locks up my
> system and forces a hard reset.  Generally it happens when something has
> been writing a lot over nfs, though sometimes it's happened while I wasn't
> around.  I tried a few commands that do i/o, and they get blocked in
> various states:
>
> (dd read file from pool) load: 0.37  cmd: dd 91214 [vq->vq_lock] 64.87r
> 0.00u 0.01s 0% 2160k
> (sync) load: 0.20  cmd: csh 92333 [buf_hash_table.ht_locks[i].ht_lock]
> 5.58r 0.00u 0.00s 0% 4548k
> (zfs unmount) load: 0.08  cmd: zfs 93685 [ds->ds_opening_lock] 4.69r 0.00u
> 0.00s 0% 4060k
>
> I was able to capture some results of procstat -kk -a, those are attached.
>
> Other info:
> # uname -a
> FreeBSD freenas.jagels.us 11.2-STABLE FreeBSD 11.2-STABLE #0
> r325575+3b66a34f3aa(HEAD): Thu Feb 14 13:40:20 EST 2019
>  root at nemesis.tn.ixsystems.com:/freenas-releng/freenas/_BE/objs/freenas-releng/freenas/_BE/os/sys/FreeNAS.amd64
> amd64
>
> Motherboard: Gigabyte GA-7PESH2 (using the onboard LSI SAS controllers)
> Cpu: 2x E5-2660 v2 HT disabled
> Storage: 6x WD-80EMAZ 4x WD20EARX 1x SanDisk SDSSDA120G
> 2x WDS500G2X0C-00L350
>
> Attached dmidecode/sysctl information as well.  I'll be happy to provide
> additional information as needed.
>
> Thanks,
> Will
>