Re: ZFS not caching right?

On 9/10/07, Pawel Jakub Dawidek <pjd_at_freebsd.org> wrote:
> On Thu, Sep 06, 2007 at 08:48:53PM +0200, Ulrich Spoerlein wrote:
> > Hi, it's me again with another stupid question,
> >
> > ever since I switched my /usr and /home to ZFS, the system has become
> > _very_ unresponsive under load. This is not because of CPU load, but I/O
> > load.
>
> Can you try recent HEAD? I committed a change that allows ZFS cache
> (ARC) to use more memory. This should be safe after dfr_at_'s vnode leak
> fix and should also help performance.
>
> --
> Pawel Jakub Dawidek                       http://www.wheel.pl
> pjd_at_FreeBSD.org                           http://www.FreeBSD.org
> FreeBSD committer                         Am I Evil? Yes, I Am!
>
>

This happened 1 day after compiling new sources:
panic: kmem_malloc(90112): kmem_map too small: 329805824 total allocated
when writing through NFS.
On FreeBSD xeon.bsdtech.org 7.0-CURRENT FreeBSD 7.0-CURRENT #8: Tue
Sep 11 00:08:39 WEST 2007
root_at_xeon.bsdtech.org:/usr/obj/usr/src/sys/GENERIC  i386
Machine has 1GB of ram and:
vfs.zfs.arc_min: 16777216
vfs.zfs.arc_max: 251658240
vfs.zfs.mdcomp_disable: 0
vfs.zfs.prefetch_disable: 1
vfs.zfs.zio.taskq_threads: 0
vfs.zfs.recover: 0
vfs.zfs.vdev.cache.size: 10485760
vfs.zfs.vdev.cache.max: 16384
vfs.zfs.cache_flush_disable: 0
vfs.zfs.zil_disable: 0
vfs.zfs.debug: 0

I hadn't had any panics with sources from August 16 but before your
recent changes vfs.zfs.arc_max was 167772160
kern.maxvnodes is not set to 50000 as recomended ( on purpose ) and is
currently at 52242 set by the system. Is 50000 still recomended after
your changes?

-- 
Joao Barros