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Date: Thu, 10 Aug 2023 14:14:42 +0200
From: Kurt Jaeger <pi@freebsd.org>
To: current@freebsd.org
Subject: Re: ZFS deadlock in 14
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References: <86leeltqcb.fsf@ltc.des.no>
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Hi!

> > At some point between 42d088299c (4 May) and f0c9703301 (26 June), a
> > deadlock was introduced in ZFS.  It is still present as of 9c2823bae9 (4
> > August) and is 100% reproducable just by starting poudriere bulk in a
> > 16-core VM and waiting a few hours until deadlkres kicks in.
> 
> I have a amd based builder, 32 cores, run 437e1e37dfca from
> Thu Jul 27 01:26:39 CEST 2023 and do not see those crashes.
> 
> zpool get feature@block_cloning zroot
> NAME   PROPERTY               VALUE                  SOURCE
> zroot  feature@block_cloning  enabled                local

se@ told me about yet another tunable 8-)

sysctl vfs.zfs.bclone_enabled   
vfs.zfs.bclone_enabled: 0

So while it's enabled in ZFS itself, it's not really active in my
system.

-- 
pi@opsec.eu            +49 171 3101372                    Now what ?