Date: Mon, 2 Nov 1998 10:21:33 -0700 (MST) From: David G Andersen <danderse@cs.utah.edu> To: jwd@unx.sas.com (John W. DeBoskey) Cc: danderse@cs.utah.edu, freebsd-hackers@FreeBSD.ORG Subject: Re: nfs/amd hangs / getattr request flood problem Message-ID: <199811021721.KAA01674@lal.cs.utah.edu> In-Reply-To: <199811011853.NAA15179@bb01f39.unx.sas.com> from "John W. DeBoskey" at Nov 1, 98 01:53:46 pm
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Nope - we're seeing a different problem. The only "huge quantities of
traffic" we're getting are traffic from the kernel to the local 'amd'.
Your patch doesn't change that (just tested it).
I'm about to grab the previous AMD out of the attic as Mike suggested, and
we'll see how that goes.
-Dave
Lo and behold, John W. DeBoskey once said:
>
> Hi,
>
> I've sent mail to -current a few times... Try the following
> change on your FreeBSD client machine(s):
>
> /usr/src/sys/nfs/nfs_vnops.c:
> 273c273
> < int v3 = NFS_ISV3(vp);
> ---
> > int v3 = 0; /* NFS_ISV3(vp); */
>
> ie: Turn off the 'access' portion of the v3 protocol.
>
> I have a build farm of about 50 266Mhz machines talking to Network
> Appliance fileservers. Without the above change, the network is
> swamped...
>
> Good Luck!
> John
>
>
> > We're in the process of configuring some new machines (for personal and
> > distributed build farm use), and we're seeing some atrocities with amd.
> > The machines are running 3.0-RELEASE (plus the last few days of checked in
> > fixes). They receive AMD maps via NIS and a static map, but disabling NIS
> > doesn't affect things. We've made significant tweaks to the rest of the
> > system configuration (disabling nis, mfs, slowing things down, etc) and
> > tried it on multiple systems, and the problem keeps popping up. This
> > behavior isn't exhibited in 2.2.x.
> >
> > We have AMD looking at /n/{machine}/path, with the actual mounts on
> > /a/{machine}. When compiling with a source tree on /n/machine/path and an
> > object tree on local /z, AMD can use up to 50% of the processor. Ktrace
> > and tcpdump output shows that it's handling around 150 getattr requests
> > per second, on "/n" and "/n/machine", and the ktrace indicates that that's
> > the _only_ thing it's doing.
> >
> > The result of this is some serious slowdowns, and reproducible system
> > freezes (kernel alive and pingable, no userland activity whatsoever).
> > Unfortunately, we don't have a simple way of reproducing the hangs yet -
> > it happens while running the Linux suse Matrox Xserver and the FreeBSD
> > netscape (entering, then leaving, and then re-entering Netscape frequently
> > triggers the hang).
> >
> > There don't seem to be any references to this in gnats or on the lists.
> > We're working on forward-porting the 2.2.x amd to 3.0 to see if the
> > behavior still exists, but in the meantime, if anyone has suggestions /
> > thoughts / knows what's wrong and wants to clue me in, it'd be greatly
> > appreciated. :)
> >
> > -Dave
> >
> > - --
> > work: danderse@cs.utah.edu me: angio@pobox.com
> > University of Utah http://www.angio.net/
> > Department of Computer Science
> >
> > To Unsubscribe: send mail to majordomo@FreeBSD.org
> > with "unsubscribe freebsd-hackers" in the body of the message
> >
> > ------------------------------
> >
>
--
work: danderse@cs.utah.edu me: angio@pobox.com
University of Utah http://www.angio.net/
Department of Computer Science
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