From owner-freebsd-performance@FreeBSD.ORG Fri Dec 14 04:24:33 2007 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9BB3C16A41A for ; Fri, 14 Dec 2007 04:24:33 +0000 (UTC) (envelope-from shantanu_ghosh@yahoo.com) Received: from web54507.mail.re2.yahoo.com (web54507.mail.re2.yahoo.com [206.190.49.157]) by mx1.freebsd.org (Postfix) with SMTP id 5C81413C43E for ; Fri, 14 Dec 2007 04:24:33 +0000 (UTC) (envelope-from shantanu_ghosh@yahoo.com) Received: (qmail 7018 invoked by uid 60001); 14 Dec 2007 04:24:32 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:Date:From:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-ID; b=R6Nw46T4uXy7gs96oxLpSHYTeQl9reiLnzr99POhPHgei3xypTfZFrxZtJ1MUF16BhFOIYQ20QxoIhn8uajDPp+MH70XpwzuQZB3Ul4iDIsA7Dmw9ZENqiCKs5ahxM1RH1+hyvdMUVkVEbbq8t613uqMnwteo3FpBh9YN81zJmE=; X-YMail-OSG: ptzJewwVM1lqBPBZxO2fqy3VbZuH6E4B43xFpoZxG7dUD4ibcZLdZ61GyyhkySk6Aw-- Received: from [203.145.181.122] by web54507.mail.re2.yahoo.com via HTTP; Thu, 13 Dec 2007 20:24:32 PST Date: Thu, 13 Dec 2007 20:24:32 -0800 (PST) From: Shantanu Ghosh To: Erich Dollansky In-Reply-To: <4761F963.5040505@pacific.net.sg> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Message-ID: <344260.5397.qm@web54507.mail.re2.yahoo.com> Cc: freebsd-performance@freebsd.org Subject: Re: freebsd vs linux: performance problem X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Dec 2007 04:24:33 -0000 --- Erich Dollansky wrote: > Hi, > > Shantanu Ghosh wrote: > > --- Erich Dollansky wrote: > > > >> Don't you call memcpy? > > > > Well, I first did - then I wrote a function to do the same, just to > > make sure that the code executed is exactly the same in both the > cases. > > The difference was there both when using memcpy, and when using the > > replacement function. > > Do you have Linux compatibility installed on the FreeBSD machine? > > You should then be able to run the Linux binary to see what happens > then. > > I have had once the problem of a task moving from CPU to CPU and s > performing badly on FreeBSD. > > I am not informed how this is handled currently. This could be something I am facing. I noticed that when I run vmstat while running this code, on linux, there's hardly any perceptible difference in the number of context switches, but on freebsd, the number of context switches in the system seems to go up a bit. However, this is not very reliable. Do you know how I can check this migration? > > I also assume that this example is a single-threaded program which > should perform just fine on single CPU machine. > > One other thing, can you just boot up with one CPU and one core to > see > what happens then? While I have not tried it on this machine, on a single cpu machine, the non-SMP build of freebsd seems to perform as well as linux for this kind of test. Thanks a lot for your help. > > Erich > _______________________________________________ > freebsd-performance@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-performance > To unsubscribe, send any mail to > "freebsd-performance-unsubscribe@freebsd.org" > -- Shantanu. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ