Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 16 Jun 2015 06:21:34 +0000
From:      bugzilla-noreply@freebsd.org
To:        freebsd-fs@FreeBSD.org
Subject:   [Bug 199189] SWAP on ZFS can crash server
Message-ID:  <bug-199189-3630-RfXZu7YQ98@https.bugs.freebsd.org/bugzilla/>
In-Reply-To: <bug-199189-3630@https.bugs.freebsd.org/bugzilla/>
References:  <bug-199189-3630@https.bugs.freebsd.org/bugzilla/>

next in thread | previous in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=199189

--- Comment #16 from Marcus Reid <marcus@blazingdot.com> ---
As for the machine in my last comment, I've tuned the problem away and I'd like
to share how:

vm.v_free_target=60000
vm.v_free_min=55000
vm.v_free_severe=50000
vm.v_free_reserved=32000
vfs.zfs.arc_free_target=180000

Now, free memory never gets down below about 50MB or so, and normally stays up
above 150MB even when under pressure and swapping.  I'm swapping to a zvol with
all of the swap tunables set.

The default values for these look more like:

vm.v_free_target: 42948
vm.v_free_min: 12741
vm.v_free_severe: 7706
vm.v_free_reserved: 2672
vfs.zfs.arc_free_target: 14014

Note that I increased vm.v_free_reserved quite a bit, but I don't know exactly
what that one does.

vm.v_free_reserved: Pages reserved for deadlock

The description seems to make it a prime candidate for tuning in this
situation, so even though nobody has mentioned it yet I raised it.

Things work great. I will post again if I manage to break it again.

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



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-199189-3630-RfXZu7YQ98>