From owner-freebsd-stable@FreeBSD.ORG Wed May 18 05:58:47 2011 Return-Path: Delivered-To: stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 02AF51065672 for ; Wed, 18 May 2011 05:58:47 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 417DE8FC19 for ; Wed, 18 May 2011 05:58:45 +0000 (UTC) Received: from porto.topspin.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id IAA11777; Wed, 18 May 2011 08:58:38 +0300 (EEST) (envelope-from avg@FreeBSD.org) Received: from localhost.topspin.kiev.ua ([127.0.0.1]) by porto.topspin.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1QMZmI-000AJK-Cb; Wed, 18 May 2011 08:58:38 +0300 Message-ID: <4DD3600D.6000709@FreeBSD.org> Date: Wed, 18 May 2011 08:58:37 +0300 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.17) Gecko/20110503 Lightning/1.0b2 Thunderbird/3.1.10 MIME-Version: 1.0 To: Charles Sprickman References: <20110517073029.GA44359@icarus.home.lan> <4DD25264.8040305@FreeBSD.org> <20110517112952.GA48610@icarus.home.lan> <4DD2624A.9080708@FreeBSD.org> <20110517122323.GA49650@icarus.home.lan> <4DD26C49.4010108@FreeBSD.org> In-Reply-To: X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: stable@FreeBSD.org, Jeremy Chadwick Subject: Re: 8.1R possible zfs snapshot livelock? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 May 2011 05:58:47 -0000 on 18/05/2011 04:49 Charles Sprickman said the following: > On Tue, 17 May 2011, Andriy Gapon wrote: >> Less drastic approach to hanged I/O debugging is to find out where >> processes/threads are actually stuck. E.g. using procstat -kk. > > Odd you say that because we've got an old 32-bit 8.1 box that's running > spamassassin and some devel stuff that looks like it's getting a little wedged: > > PID USERNAME THR PRI NICE SIZE RES STATE TIME WCPU COMMAND > 6 root 4 -8 - 0K 36K tx->tx 126.0H 76.37% zfskern > > And I'm not sure "procstat" is meant for this, but the output is interesting: It is. > [root@h22 /home/spork]# procstat -k 6 > PID TID COMM TDNAME KSTACK > 6 100053 zfskern arc_reclaim_thre mi_switch sleepq_switch > sleepq_timedwait _cv_timedwait arc_reclaim_thread fork_exit fork_trampoline > 6 100054 zfskern l2arc_feed_threa mi_switch sleepq_switch > sleepq_timedwait _cv_timedwait l2arc_feed_thread fork_exit fork_trampoline > 6 100093 zfskern txg_thread_enter mi_switch sleepq_switch > sleepq_wait _cv_wait txg_thread_wait txg_quiesce_thread fork_exit fork_trampoline > 6 100094 zfskern txg_thread_enter mi_switch sleepq_switch > sleepq_timedwait _cv_timedwait txg_thread_wait txg_sync_thread fork_exit > fork_trampoline This looks completely normal. -- Andriy Gapon