ZFS with compression causes deadlock

[Claus Guttesen]

> Today I had deadlock on several machines. Almost all processes stucked in
> [tx->tx_cpu[c].tc_lock]. Machines were helped only `reboot -n'.
> I've created new gzip-ed filesystem a few days ago. I didn't have any
> problems with ZFS before.
>
> System was built from svn://svn.freebsd.org/base/stable/8@215508.
> Machines have 24Gb RAM, 4 SATA 500Gb disks in raidz.
>
> loader.conf:
> ahci_load="YES"
> zfs_load="YES"
> vfs.zfs.arc_max="2G"
> vfs.zfs.cache_flush_disable="1" # default: 0
> vfs.zfs.prefetch_disable="1"    # default: 0
> vfs.zfs.txg.timeout="5"         # default: 30
> vfs.zfs.zio.use_uma="0"         # default: 0 (earlier was 1)

Have you tried to remove vfs.zfs.* in rc.conf? Newer versions of zfs
may not need tuning except in specific cases now.

I've had problems using compression in (much) earlier zfs-versions
some years ago and avoided this feature. A few days ago I've setup
FreeBSD current with zfs. ver. 28 and enabled compression and have
performed a zfs receive with approx. 660 GB of data that boils down to
350 GB without problems.

-- 
regards
Claus

When lenity and cruelty play for a kingdom,
the gentler gamester is the soonest winner.

Shakespeare

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