From owner-freebsd-current@FreeBSD.ORG Wed Jan 28 09:36:41 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 605DC16A4CF for ; Wed, 28 Jan 2004 09:36:41 -0800 (PST) Received: from tx2.oucs.ox.ac.uk (tx2.oucs.ox.ac.uk [163.1.2.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 14D3A43D48 for ; Wed, 28 Jan 2004 09:36:37 -0800 (PST) (envelope-from colin.percival@wadham.ox.ac.uk) Received: from scan2.oucs.ox.ac.uk ([163.1.2.162] helo=localhost) by tx2.oucs.ox.ac.uk with esmtp (Exim 4.24) id 1AltcC-00078U-K6 for freebsd-current@freebsd.org; Wed, 28 Jan 2004 17:36:36 +0000 Received: from rx2.oucs.ox.ac.uk ([163.1.2.161]) by localhost (scan2.oucs.ox.ac.uk [163.1.2.162]) (amavisd-new, port 25) with ESMTP id 27334-06 for ; Wed, 28 Jan 2004 17:36:36 +0000 (GMT) Received: from gateway.wadham.ox.ac.uk ([163.1.161.253]) by rx2.oucs.ox.ac.uk with smtp (Exim 4.24) id 1AltcC-00078R-6i for freebsd-current@freebsd.org; Wed, 28 Jan 2004 17:36:36 +0000 Received: (qmail 28456 invoked by uid 0); 28 Jan 2004 17:36:35 -0000 Received: from colin.percival@wadham.ox.ac.uk by gateway by uid 71 with qmail-scanner-1.16 (sweep: 2.14/3.71. spamassassin: 2.53. Clear:. Processed in 1.340156 secs); 28 Jan 2004 17:36:35 -0000 X-Qmail-Scanner-Mail-From: colin.percival@wadham.ox.ac.uk via gateway X-Qmail-Scanner: 1.16 (Clear:. Processed in 1.340156 secs) Received: from dhcp1131.wadham.ox.ac.uk (HELO piii600.wadham.ox.ac.uk) (163.1.161.131) by gateway.wadham.ox.ac.uk with SMTP; 28 Jan 2004 17:36:34 -0000 Message-Id: <6.0.1.1.1.20040128173146.03f29ad0@imap.sfu.ca> X-Sender: cperciva@imap.sfu.ca (Unverified) X-Mailer: QUALCOMM Windows Eudora Version 6.0.1.1 Date: Wed, 28 Jan 2004 17:36:21 +0000 To: Don Bowman From: Colin Percival In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed cc: "'freebsd-current@freebsd.org'" Subject: Re: system call performance 4.x vs 5.x [and UP vs MP] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Jan 2004 17:36:41 -0000 At 17:20 28/01/2004, Don Bowman wrote: >For example, on a 2.0GHz P4-Xeon, HTT enabled, MP kernel, i can >do ~1M socket/s calls on 4.7, but only ~250K/s on 5.2. > > syscall 4.7 5.2 > write 1015036 169800 > socket 1078994 223253 > select 430564 155077 >gettimeofday 252762 183620 > >Any suggestion on why such a difference between 4.x and 5.x? Mutexes are slow. The SMP changes in 5.x result in much better scaling, but there is some inevitable overhead cost. Colin Percival