From owner-freebsd-current@FreeBSD.ORG Fri Jul 29 21:45:08 2005 Return-Path: X-Original-To: freebsd-current@freebsd.org 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 745F416A41F for ; Fri, 29 Jul 2005 21:45:08 +0000 (GMT) (envelope-from peterjeremy@optushome.com.au) Received: from mail13.syd.optusnet.com.au (mail13.syd.optusnet.com.au [211.29.132.194]) by mx1.FreeBSD.org (Postfix) with ESMTP id BF51F43D45 for ; Fri, 29 Jul 2005 21:45:07 +0000 (GMT) (envelope-from peterjeremy@optushome.com.au) Received: from server.vk2pj.dyndns.org (c220-239-19-236.belrs4.nsw.optusnet.com.au [220.239.19.236]) by mail13.syd.optusnet.com.au (8.12.11/8.12.11) with ESMTP id j6TLiu3E011854 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Sat, 30 Jul 2005 07:44:56 +1000 Received: from server.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by server.vk2pj.dyndns.org (8.13.1/8.13.1) with ESMTP id j6TLitSM029866; Sat, 30 Jul 2005 07:44:55 +1000 (EST) (envelope-from peter@server.vk2pj.dyndns.org) Received: (from peter@localhost) by server.vk2pj.dyndns.org (8.13.1/8.13.1/Submit) id j6TLio2p029865; Sat, 30 Jul 2005 07:44:50 +1000 (EST) (envelope-from peter) Date: Sat, 30 Jul 2005 07:44:50 +1000 From: Peter Jeremy To: Julian Elischer Message-ID: <20050729214450.GB81215@server.vk2pj.dyndns.org> References: <42E88135.30603@elischer.org> <42E88F2B.5000108@elischer.org> <20050728082844.GW46538@darkness.comp.waw.pl> <42E898A6.6010803@elischer.org> <20050728115251.GA20091@beatrix.daedalusnetworks.priv> <20050728135613.GD46538@darkness.comp.waw.pl> <42E93EE1.2090009@elischer.org> <42E94310.20806@samsco.org> <42E94A88.4010603@elischer.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42E94A88.4010603@elischer.org> User-Agent: Mutt/1.4.2.1i Cc: FreeBSD Current Subject: Re: 6.0 VFS/VM over-runs. Was: Apparent strange disk behaviour in 6.0 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Fri, 29 Jul 2005 21:45:08 -0000 [CC list pruned] On Thu, Jul 28, 2005 at 02:13:44PM -0700, Julian Elischer wrote: >file data written to cache to await output to disk is allowed to grow to >the extent that running programs are swapped out. >(or at least paged out). I don't see this on 5.3 either. In multi-user mode (with lots of other processes sitting aroung idle) vmstat shows fr and sr sit at around 10,000/sec but there's no paging and a "ps -axl" afterwards shows everything mostly still resident. The active memory (avm) hardly changes but free memory drops from 233MB to 20MB over 8 seconds than oscillates between about 16MB and 30MB. Disk I/O remains at 35-40MB/sec (ie disk limited). This is an Athlon XP-1800 512MB RAM writing a 10GB file onto an ATA disk. PREEMPTION is enabled. Since Marc Olzheim reports it happens with 5-STABLE and Julian reports it doesn't happen on 5.4 and I can't reproduce it on 5.3, one option would seem to be that it was MFC'd to 5 at some point since 5.4 was branched. Unfortunately, a quick scan through the RELENG_5 commits doesn't reveal anything that might be relevant. The other possibility is that it's RAM size related. The vmstat output Julian posted demonstrating the problem was on a system with a fair bit of RAM, but his 5.4 system is presumably smaller and my system definitely is. -- Peter