From owner-freebsd-performance@FreeBSD.ORG  Sun Jun 11 21:37:04 2006
Return-Path: <owner-freebsd-performance@FreeBSD.ORG>
X-Original-To: performance@freebsd.org
Delivered-To: freebsd-performance@FreeBSD.ORG
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 59C1116A418;
	Sun, 11 Jun 2006 21:37:04 +0000 (UTC) (envelope-from scrappy@hub.org)
Received: from hub.org (hub.org [200.46.204.220])
	by mx1.FreeBSD.org (Postfix) with ESMTP id E2BB743D46;
	Sun, 11 Jun 2006 21:37:03 +0000 (GMT) (envelope-from scrappy@hub.org)
Received: from localhost (mx1.hub.org [200.46.208.251])
	by hub.org (Postfix) with ESMTP id F3049290C25;
	Sun, 11 Jun 2006 18:36:59 -0300 (ADT)
Received: from hub.org ([200.46.204.220])
	by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024)
	with ESMTP id 58527-06; Sun, 11 Jun 2006 18:37:03 -0300 (ADT)
Received: from ganymede.hub.org (blk-7-151-244.eastlink.ca [71.7.151.244])
	by hub.org (Postfix) with ESMTP id 743C2290C20;
	Sun, 11 Jun 2006 18:36:59 -0300 (ADT)
Received: by ganymede.hub.org (Postfix, from userid 1000)
	id DDFAB3EC22; Sun, 11 Jun 2006 18:37:05 -0300 (ADT)
Received: from localhost (localhost [127.0.0.1])
	by ganymede.hub.org (Postfix) with ESMTP id D53553EA1B;
	Sun, 11 Jun 2006 18:37:05 -0300 (ADT)
Date: Sun, 11 Jun 2006 18:37:05 -0300 (ADT)
From: "Marc G. Fournier" <scrappy@hub.org>
To: Kris Kennaway <kris@obsecurity.org>
In-Reply-To: <20060611174527.GA31119@xor.obsecurity.org>
Message-ID: <20060611183544.D1114@ganymede.hub.org>
References: <20060611174527.GA31119@xor.obsecurity.org>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Cc: scrappy@FreeBSD.org, performance@FreeBSD.org
Subject: Re: Postgresql performance profiling
X-BeenThere: freebsd-performance@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Performance/tuning <freebsd-performance.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-performance>,
	<mailto:freebsd-performance-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-performance>
List-Post: <mailto:freebsd-performance@freebsd.org>
List-Help: <mailto:freebsd-performance-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-performance>,
	<mailto:freebsd-performance-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 11 Jun 2006 21:37:04 -0000

On Sun, 11 Jun 2006, Kris Kennaway wrote:

> * The postgres processes seem to change their proctitle hundreds or 
> thousands of times per second.  This is currently done via a 
> Giant-locked sysctl (kern.proc.args) so there is enormous contention for 
> Giant.  Even when this is fixed (thanks to a patch from csjp@), each of 
> them requires a syscall and syscalls ain't free.  This is not a clever 
> thing to be doing from a performance standpoint.

to disable for testing, after you run configure, manually edit 
src/include/pg_config.h and undef HAVE_SETPROCTITLE ...

----
Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
Email . scrappy@hub.org                              MSN . scrappy@hub.org
Yahoo . yscrappy               Skype: hub.org        ICQ . 7615664