From owner-freebsd-hackers@FreeBSD.ORG  Tue Jun  8 17:36:30 2004
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP
	id D0C6A16A4CE; Tue,  8 Jun 2004 17:36:30 +0000 (GMT)
Received: from fledge.watson.org (fledge.watson.org [204.156.12.50])
	by mx1.FreeBSD.org (Postfix) with ESMTP
	id 7B4FE43D39; Tue,  8 Jun 2004 17:36:30 +0000 (GMT)
	(envelope-from robert@fledge.watson.org)
Received: from fledge.watson.org (localhost [127.0.0.1])
	by fledge.watson.org (8.12.11/8.12.11) with ESMTP id i58HZVJZ077839;
	Tue, 8 Jun 2004 13:35:31 -0400 (EDT)
	(envelope-from robert@fledge.watson.org)
Received: from localhost (robert@localhost)i58HZVkd077836;
	Tue, 8 Jun 2004 13:35:31 -0400 (EDT)
	(envelope-from robert@fledge.watson.org)
Date: Tue, 8 Jun 2004 13:35:31 -0400 (EDT)
From: Robert Watson <rwatson@FreeBSD.org>
X-Sender: robert@fledge.watson.org
To: Ali Niknam <ali@transip.nl>
In-Reply-To: <00bd01c44cb5$ccf5f840$0400a8c0@redguy>
Message-ID: <Pine.NEB.3.96L.1040608133448.75106C-100000@fledge.watson.org>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
cc: freebsd-hackers@FreeBSD.org
cc: John Baldwin <jhb@FreeBSD.org>
Subject: Re: FreeBSD 5.2.1: Mutex/Spinlock starvation?
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 08 Jun 2004 17:36:30 -0000

On Mon, 7 Jun 2004, Ali Niknam wrote:

> > There isn't a timeout.  Rather, the lock spins so long as the current
> > owning thread is executing on another CPU.
> 
> Interesting. Is there a way to 'lock' CPU's so that they always run on
> 'another' CPU ?
> 
> Unfortunately as we speak the server is down again :( This all makes me
> wonder wether I should simply go back to 4.10.
> I decreased the maximum number of apache children to 1400 and the server
> seems to be barely holding on:
> last pid:  2483;  load averages: 75.77, 28.63, 11.40    up 0+00:04:32
> 19:35:07
> 1438 processes:2 running, 294 sleeping, 1142 lock
> CPU states:  6.2% user,  0.0% nice, 62.6% system,  7.5% interrupt, 23.8%
> idle
> Mem: 698M Active, 27M Inact, 209M Wired, 440K Cache, 96M Buf, 1068M Free
> Swap: 512M Total, 512M Free
> 
> Are there anymore quite stable things to do ? That is except for upping
> to current, which I frankly feel is too dangerous... 

Is there any way you can give us a "top -S" output snapshot of your full
set of processes, if necessary omitting sensitive process names, etc?

Also, can you give a snapshot of "vmstat -systat" once it's settled for a
few iterations?

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Senior Research Scientist, McAfee Research