Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 15 Dec 2001 13:17:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 15 Dec 2001 13:17:20 -0500 Received: from mustard.heime.net ([194.234.65.222]:17103 "EHLO mustard.heime.net") by vger.kernel.org with ESMTP id ; Sat, 15 Dec 2001 13:17:11 -0500 Date: Sat, 15 Dec 2001 19:16:41 +0100 (CET) From: Roy Sigurd Karlsbakk To: Jens Axboe cc: Mark Hahn , Subject: Re: [BUG] RAID sub system In-Reply-To: <20011214165303.GK1180@suse.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > sysrq-t output from a "hung" system would give some valuable info as to > why it's stuck. It never hangs. It just slows down the i/o to ~ 1MB/s also ... I started out with 200 'dd' processes (as the script I sent earlier). The i/o gets stuck, and ... strange ... # killall dd watching vmstat procs memory swap io system cpu r b w swpd free buff cache si so bi bo in cs us sy id 0 200 0 0 3280 4092 782072 0 0 1054 0 621 657 0 4 96 0 200 0 0 3284 4092 782108 0 0 1042 0 631 665 1 1 98 0 101 0 0 3672 4164 804600 0 0 17594 0 762 931 2 9 88 0 56 1 0 3248 4180 815332 0 0 32598 0 897 727 0 10 90 0 30 1 0 3276 4212 821640 0 0 33102 40 910 447 1 6 92 0 1 1 0 3252 4236 829080 0 0 31692 0 947 301 1 9 90 0 0 0 0 3296 4236 829320 0 0 2042 0 401 132 0 0 100 0 0 0 0 3288 4244 829320 0 0 0 26 360 132 0 0 100 0 0 0 0 3288 4244 829320 0 0 0 0 326 127 0 0 100 0 0 0 0 3288 4244 829320 0 0 0 0 358 127 0 0 100 It speeds up again when the processes start to die, although the number of processes started has no effect of the outcome. After a while the i/o stops completely up (see above lines 1,2). I also noted a quite a dramatic speed reduction in 2.4.17-rc1 compared to 2.4.16. 2.4.16 gave me up to 50 megs / sec, wheras 2.4.17-rc1 only gives me around 35. roy -- Roy Sigurd Karlsbakk, MCSE, MCNE, CLS, LCA Computers are like air conditioners. They stop working when you open Windows. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/