From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 25 May 2001 20:25:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 25 May 2001 20:25:23 -0400 Received: from dewey.mindlink.net ([204.174.16.4]:60684 "EHLO dewey.paralynx.net") by vger.kernel.org with ESMTP id ; Fri, 25 May 2001 20:25:05 -0400 Subject: Re: PROBLEM: Alpha SMP Low Outbound Bandwidth From: Jay Thorne To: George France Cc: linux-kernel@vger.kernel.org In-Reply-To: <01052519312101.28075@shadowfax.middleearth> In-Reply-To: <990827407.27355.2.camel@gracie.userfriendly.org> <01052518523300.28075@shadowfax.middleearth> <990831934.27357.4.camel@gracie.userfriendly.org> <01052519312101.28075@shadowfax.middleearth> Content-Type: text/plain X-Mailer: Evolution/0.10 (Preview Release) Date: 25 May 2001 17:25:03 -0700 Message-Id: <990836703.27355.6.camel@gracie.userfriendly.org> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 25 May 2001 19:31:21 -0400, George France wrote: > On Friday 25 May 2001 19:05, Jay Thorne wrote: > > On 25 May 2001 18:52:33 -0400, George France wrote: > > > Hello Jay, > > > > > > I see that you are using the tulip driver. Could you try the de4x5 > > > driver?? > > > > Its worse: reports 3.1 MBs and 1.6 MBs > > wuftp is not exactly a performance benchmark, have you tried 'netperf'? > > --George While I agree with you completely that wuftpd is not exactly a performance leader, this is the simplest way to recreate a problem I was having with a much more complex setup involving apache and SMP and a whole bunch of things. I posted 2 weeks ago and got no response, I assume because everyone thought it was my software. After reducing the problem to eliminate the possibility that my code is the real problem, I'm left with a quite repeatable state. I have two nearly identical machines, one with 466 mhz cpus the other with 400mhz, and they both do the same thing. The via-rhine performs similarly to the de4x5. Netperf is a pretty good idea. Should not be a cpu bottleneck. Thats a good thing. So pretty much the same results as wu-ftpd: Note that I used the 466 mhz quad with a via-rhine, since the 400 locked up and was still fscking when I started this test. Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec To alpha 87380 16384 16384 10.02 39.25 x86 local 87380 16384 16384 9.99 559.46 alpha local 87380 16384 16384 10.01 547.27 alp to x86 87380 16384 16384 10.01 25.77 another x86 87380 16384 16384 9.99 553.67 to same x86 87380 16384 16384 10.00 82.79 and back 87380 16384 16384 10.00 93.89 But Wu-ftpd is an easy to set up test bench, and is ubiquitous enough that anyone with an alpha running SMP can test it. Note that this software and the server in question were tested to run at 10+ megabytes per second with x86 boxes. The server is a PIII500 running 2.4.4, so its not like I'm comparing apples to oranges. The second x86 is an athlon 600. So even factoring out wuftp is not helping much here. I'm fairly convinced that something is strange because after the de4x5 test, the box locked up. So either a> I have two identically boned 4 cpu boxen or b> the interprocessor/locking/resource management has some kind of problem. Note that under uniprocessor I get near identical to x86 performance, clock for clock and no lock ups. -- -- Jay Thorne Manager, Systems & Technology, UserFriendly Media, Inc.