From owner-freebsd-current@FreeBSD.ORG Fri May 15 18:29:45 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 742B21065672; Fri, 15 May 2009 18:29:45 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 45DFA8FC28; Fri, 15 May 2009 18:29:45 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id EF01146C16; Fri, 15 May 2009 14:29:44 -0400 (EDT) Received: from jhbbsd.hudson-trading.com (unknown [209.249.190.8]) by bigwig.baldwin.cx (Postfix) with ESMTPA id 7D3428A02A; Fri, 15 May 2009 14:29:43 -0400 (EDT) From: John Baldwin To: Ben Kelly Date: Fri, 15 May 2009 14:26:00 -0400 User-Agent: KMail/1.9.7 References: <9A637B27-7C89-49BA-8385-A5B2D5D54BB3@wanderview.com> <200905121028.58998.jhb@freebsd.org> <6A55FF0C-EEE2-473A-867C-489E3F18463D@wanderview.com> In-Reply-To: <6A55FF0C-EEE2-473A-867C-489E3F18463D@wanderview.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200905151426.00489.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0.1 (bigwig.baldwin.cx); Fri, 15 May 2009 14:29:43 -0400 (EDT) X-Virus-Scanned: clamav-milter 0.95 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-2.5 required=4.2 tests=AWL,BAYES_00,RDNS_NONE autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on bigwig.baldwin.cx Cc: freebsd-current@freebsd.org, Robert Watson Subject: Re: [patch] corrupt memstat_kvm_malloc(3) output and dtrace 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, 15 May 2009 18:29:45 -0000 On Friday 15 May 2009 1:17:09 pm Ben Kelly wrote: > On May 12, 2009, at 10:28 AM, John Baldwin wrote: > > On Wednesday 06 May 2009 1:00:09 am Ben Kelly wrote: > >> On May 5, 2009, at 10:18 AM, Ben Kelly wrote: > >>> While debugging a problem recently with Alexander Leidinger we > >>> noticed that crashinfo(8) was producing corrupt vmstat -m output. > >>> After doing some digging it appears that memstat_kvm_malloc(3) might > >>> have been broken by this commit: > >>> > >>> http://svn.freebsd.org/viewvc/base?view=revision&revision=179222 > >>> > >>> The problem is that memstat_kvm_malloc(3) assumes that > >>> malloc_type_internal starts with an array of malloc_types_stats > >>> structures. This assumption is no longer true, though, as > >>> mti_probes was inserted at the start of the structure. > >>> > >>> It appears that this (untested) patch might fix the problem: > >>> > >>> http://www.wanderview.com/svn/public/misc/zfs/vmstat_kvm_malloc.diff > >>> > >>> I'm not very familiar with dtrace, though. Does anyone know if this > >>> would cause problems? > >> > >> Just FYI, I was able to recompile and test this patch tonight. It > >> seems to have fixed vmstat -M $core -m output on my machine. > > > > I think that it would be better to update memstat_kvm_malloc(3) > > though. I'm > > also curious why libmemstat isn't just using malloc_types_internal > > directly. > > I've updated the patch so that memstat_kvm_malloc(3) uses the > malloc_type_internal definition to find the start of the statistics > array. This also appears to fix the problem on my server. Thanks! I've committed the fix. -- John Baldwin