Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 8 Jan 2008 23:45:57 -0600
From:      Dan Nelson <dnelson@allantgroup.com>
To:        Ivan Voras <ivoras@freebsd.org>
Cc:        Dag-Erling Smorgrav <des@des.no>, freebsd-current@freebsd.org, pjd@freebsd.org
Subject:   Re: When will ZFS become stable?
Message-ID:  <20080109054557.GB55800@dan.emsphone.com>
In-Reply-To: <9bbcef730801081516g50775926ndb43b0a8a308dafc@mail.gmail.com>
References:  <200801081758.m08HwlOg076161@lurza.secnetix.de> <861w8sp44p.fsf@ds4.des.no> <9bbcef730801081516g50775926ndb43b0a8a308dafc@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Jan 09), Ivan Voras said:
> On 08/01/2008, Dag-Erling Smorgrav <des@des.no> wrote:
> > Actually, it fails to mention the most important bit:
> > vfs.zfs.arc_max, which allows you to restrict the amount of memory
> > used by ZFS to something comfortably smaller than vm.kmem_size.
> 
> Pawel, is it recommended?
> 
> If it is, I'll add it to the page.

With the vm_kern.c.2.patch, it doesn't seem to be an issue, at least
for me.  "c" always stays far away from "c_max":

kstat.zfs.misc.arcstats.p: 218885440
kstat.zfs.misc.arcstats.c: 342346436
kstat.zfs.misc.arcstats.c_min: 20971520
kstat.zfs.misc.arcstats.c_max: 503316480
kstat.zfs.misc.arcstats.size: 342342144
vm.kmem_size: 671088640
hw.physmem: 1064771584
vm.kmem_map_panics_avoided: 171

The last sysctl was added by me to track how often the patch saved my
system from a panic :)  I suppose lowering arc_max would reduce the
number of times the routine was called, though.

-- 
	Dan Nelson
	dnelson@allantgroup.com



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080109054557.GB55800>