From owner-freebsd-questions@FreeBSD.ORG Wed Jul 6 21:00:23 2011 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id ED7DC106566C; Wed, 6 Jul 2011 21:00:23 +0000 (UTC) (envelope-from ohartman@zedat.fu-berlin.de) Received: from outpost1.zedat.fu-berlin.de (outpost1.zedat.fu-berlin.de [130.133.4.66]) by mx1.freebsd.org (Postfix) with ESMTP id A5C4A8FC16; Wed, 6 Jul 2011 21:00:23 +0000 (UTC) Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost1.zedat.fu-berlin.de (Exim 4.69) with esmtp (envelope-from ) id <1QeZCo-0004VZ-18>; Wed, 06 Jul 2011 23:00:22 +0200 Received: from e178039240.adsl.alicedsl.de ([85.178.39.240] helo=thor.walstatt.dyndns.org) by inpost2.zedat.fu-berlin.de (Exim 4.69) with esmtpsa (envelope-from ) id <1QeZCn-00026K-Tt>; Wed, 06 Jul 2011 23:00:22 +0200 Message-ID: <4E14CCE5.4050906@zedat.fu-berlin.de> Date: Wed, 06 Jul 2011 23:00:21 +0200 From: "Hartmann, O." User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:5.0) Gecko/20110630 Thunderbird/5.0 MIME-Version: 1.0 To: Steve Kargl References: <4E1421D9.7080808@zedat.fu-berlin.de> <4E147F54.40908@zedat.fu-berlin.de> <20110706162811.GA68436@troutmask.apl.washington.edu> <20110706193636.GA69550@troutmask.apl.washington.edu> In-Reply-To: <20110706193636.GA69550@troutmask.apl.washington.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: 85.178.39.240 Cc: FreeBSD Current , arrowdodger <6yearold@gmail.com>, Arnaud Lacombe , freebsd-questions@freebsd.org Subject: Re: Heavy I/O blocks FreeBSD box for several seconds X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Jul 2011 21:00:24 -0000 On 07/06/11 21:36, Steve Kargl wrote: > On Wed, Jul 06, 2011 at 03:18:35PM -0400, Arnaud Lacombe wrote: >> Hi, >> >> On Wed, Jul 6, 2011 at 12:28 PM, Steve Kargl >> wrote: >>> On Wed, Jul 06, 2011 at 05:29:24PM +0200, O. Hartmann wrote: >>>> I use SCHED_ULE on all machines, since it is supposed to be performing >>>> better on multicore boxes, but there are lots of suggestions switching >>>> back to the old SCHED_4BSD scheduler. >>>> >>> If you are using MPI in numerical codes, then you want >>> to use SCHED_4BSD. ?I've posted numerous times about ULE >>> and its very poor performance when using MPI. >>> >>> http://lists.freebsd.org/pipermail/freebsd-hackers/2008-October/026375.html >>> >> [sarcasm] >> It is rather funny to see that the post you point out has generated >> exactly 0 meaningful follow-up then and as you mention later in this >> thread, the issue still remains today :-) >> [/sarcasm] >> > Apparently, you are privy to my private email exchanges > with jeffr. > > I'm also not sure why you're being sarcastic here. The > issue was and AFAIK still is a problem for anyone using > FreeBSD in a HPC cluster. ULE simply performs worse than > 4BSD. > Well, I know only very little people using FreeBSD within a HPC cluster or even for scientific purposes, except myself and some people around here.