Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 31 Aug 2009 14:51:09 -0700
From:      Kip Macy <kmacy@freebsd.org>
To:        Simun Mikecin <numisemis@yahoo.com>
Cc:        freebsd-fs@freebsd.org
Subject:   Re: need help with ZFS
Message-ID:  <3c1674c90908311451j5650bcdfl119309368d852a49@mail.gmail.com>
In-Reply-To: <941145.26591.qm@web37302.mail.mud.yahoo.com>
References:  <4A927CB3.3040402@plus-plus.su> <4A964F4E.4080009@plus-plus.su> <941145.26591.qm@web37302.mail.mud.yahoo.com>

next in thread | previous in thread | raw e-mail | index | archive | help
>> vm.kmem_size="1536M"
>> vm.kmem_size_max="3072M"
>> vm.pmap.shpgperproc="1024"
>> vfs.zfs.arc_min="256M"
>> vfs.zfs.arc_max="384M"
>> vfs.zfs.vdev.cache.size="50M"
>> vfs.zfs.prefetch_disable="1"
>> kern.maxproc="20000"
>
> Since FreeBSD 7.2 no additional ZFS tuning in loader.conf is needed (on amd64).
> You should remove all those settings from loader.conf, reboot, and re-run the tests.
> Maybe, just maybe you get a panic just because of those settings.

Actually you probably still want to set kmem_size, kmem_size_max, and
arc_min. kmem_size_max just overrides auto-tuning it doesn't actually
raise kmem_size. I have found that the ARC can get starved out by user
processes with many pages in the page cache so a large arc_min can be
useful too. Bear in mind that kmem_size can safely be much larger than
physical memory, kmem_malloc can often fail due to KVA fragmentation
even when physical memory is plentiful.

 -Kip



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3c1674c90908311451j5650bcdfl119309368d852a49>