From owner-freebsd-current@FreeBSD.ORG Fri Dec 20 18:23:27 2013 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id DD3F0726 for ; Fri, 20 Dec 2013 18:23:27 +0000 (UTC) Received: from mail-wg0-x22b.google.com (mail-wg0-x22b.google.com [IPv6:2a00:1450:400c:c00::22b]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 76DAC1D73 for ; Fri, 20 Dec 2013 18:23:27 +0000 (UTC) Received: by mail-wg0-f43.google.com with SMTP id k14so2773242wgh.34 for ; Fri, 20 Dec 2013 10:23:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=yHgUFHpXn91FxsgNIj7PX5O+PZTLqj1VjAK7DZjiGc8=; b=qCyK1m4Ppx46/03TJ15NwnOLqGR27H0mGPz1SsFQ+H90Vb+X1y0iAaZWXx3W2JbguL hhfDAJqFT/A8UyQZuEkY8IB8OucL5mcYJ7L/2n4bdKfaaJQOD6lTzEjwSn39N3RED8Ff EPo/R4wo4PPR0ZULRe7w5Kf/wHvUe8bfDY5WswKJUMrvNejzo3dloUWiPiFuBz51rJK7 wdcs4mNPpNoU1Ky8kA98fdHzE5zX9bL+AZp2F3Lm+A/uc73XDq3FtHmNekEt0URk7wNw dBiGUh844+6XZh4geh/0m7jTHpg2mE1Rk8zZN+huQdIDW7NbuWMdQ4KqZLU+1LRU1JXm 21SQ== MIME-Version: 1.0 X-Received: by 10.194.237.99 with SMTP id vb3mr8300937wjc.28.1387563805761; Fri, 20 Dec 2013 10:23:25 -0800 (PST) Sender: asomers@gmail.com Received: by 10.194.55.101 with HTTP; Fri, 20 Dec 2013 10:23:25 -0800 (PST) In-Reply-To: <20131220115534.52e79a76@telesto> References: <20131220115534.52e79a76@telesto> Date: Fri, 20 Dec 2013 11:23:25 -0700 X-Google-Sender-Auth: uUA86Fv344zMjxgRM1q0xi8e_18 Message-ID: Subject: Re: ZFS/zpool command blocks ... locking up all terminals From: Alan Somers To: "O. Hartmann" Content-Type: text/plain; charset=ISO-8859-1 Cc: FreeBSD CURRENT X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.17 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, 20 Dec 2013 18:23:27 -0000 On Fri, Dec 20, 2013 at 3:55 AM, O. Hartmann wrote: > > I have a faulty pool with an ambiguous label and I tried to resolve > that problem. ZFS is at the moment highly active copying data from > several volumes to another. > > Operating system: > > 11.0-CURRENT FreeBSD 11.0-CURRENT #1 r259522: Tue Dec 17 19:02:10 CET > 2013 amd64 > > In one terminal I exported the pool in question and tried to list it > via "zpool import". But the this command sequence locks up the terminal > for an hour up! > > In another terminal I tried to issue to command "zpool status" to watch > the status of the pools (I have several). But this terminal ist alos > locked up right now! > > What is wrong here? I had such an issue in 10.0-CURRENT as well. It > seems ZFS is locking everything up and can only be brought back by a > hard reset! What is going on? Why is zpool locking up in trying to > display a label-scrambled pool while the zpool status is then also > locked up, but latter is supposed to show the status of the other, > healthy pools? This reminds me of single-threaded tools which looks up > every operation consecutively issued after the blocking command. > > How is this to be solved? Sounds like a deadlock. Did the "zpool export" complete successfully? Did the pool become suspended at any point? Can you get to the kernel debugger? Most importantly, can you reproduce it? If you can, you'll probably need a WITNESS enabled kernel to get any useful info. When I find a deadlock, I usually go into the kernel debugger and issue the following commands. It results in about a megabyte of output, so use screen or tmux or something to capture the output x/s version show msginfo ps alltrace show alllocks # You need witness for this one -Alan > > Oliver