From owner-freebsd-stable@FreeBSD.ORG Wed May 23 20:18:02 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C9EF91065675 for ; Wed, 23 May 2012 20:18:02 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-pz0-f54.google.com (mail-pz0-f54.google.com [209.85.210.54]) by mx1.freebsd.org (Postfix) with ESMTP id 9C79F8FC14 for ; Wed, 23 May 2012 20:18:02 +0000 (UTC) Received: by dadv36 with SMTP id v36so11083869dad.13 for ; Wed, 23 May 2012 13:18:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=A0/5HTRXKE+ZZwrRGXVCYy8IkqOb1qgP9iJD2qP39bQ=; b=YWCeUZlzFvMLTukHsQHoLosb4hEylUNE6wPSXMRp3MtjcP87WaDMcxMgUMgFwXWNFb F5TQ84WnXO6xSF3D8+bl0bOFRTyxhNb1ZPBIMoyy0GYX9icMydAEJyGMuoB5dq6ceoVO jGQfK0W07dj7EhN3joIpLq/gXlv1aKB4fG8yuxUpEOXsaShEFpHaH5wWatqLW+NxZk2j TQ+RQMBTf/3Uy8pqO2T4XiEgUq2ehTemwjBuf0wGhBxcKowcS+Eh95JRDIJI37Tbvoqj zFck5YOK2ytNnJnOO/37jXd6ZBTmK2iEGUfskxp84G6ftKUf6vye5QWIwVSfOe1iXc3f pKKg== MIME-Version: 1.0 Received: by 10.68.234.35 with SMTP id ub3mr13882730pbc.8.1337804282085; Wed, 23 May 2012 13:18:02 -0700 (PDT) Sender: adrian.chadd@gmail.com Received: by 10.142.203.2 with HTTP; Wed, 23 May 2012 13:18:02 -0700 (PDT) In-Reply-To: References: Date: Wed, 23 May 2012 13:18:02 -0700 X-Google-Sender-Auth: jYMBPWInwt8lChpm1OXbYP4TS3o Message-ID: From: Adrian Chadd To: Pete French Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: freebsd-stable@freebsd.org Subject: Re: VirtualBox, AIO and zvol's - a cautionary tale 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, 23 May 2012 20:18:02 -0000 Hi, Can you please file a PR? Having broken AIO and ZFS would be .. bad. adrian On 23 May 2012 06:11, Pete French wrote: > Am posting this to stable not really as a question, but more in case anyo= ne > else hits the same problem. Last patch tuesday one of my virtual Windows > machines =A0running under VirtualBox started crashing. By which I mean > that VirtualBox would quit. This had been running tsably for a long > tine, so it puzzled me. > > First thought was it was sme patch from patch-tuesday. But rolling back > to an earlier version of the disc showed it wasn't - the crashes were > occurring before the patch had been applied. > > I'll skip the hours of puzzlement which followed - it turrned out that > the indirect cause was that a few weeks ago I had installed Samba > onto the same server. In doing so I had enabled AIO, as this improves > Samba performance. > > What I didn't realise is that if VirtualBox finds AIO loaded it proceeds > to use it. =A0So by doing that I had switched on AIO inside my virtual > machines as well. The disc I use for my virtual machines are all zvols (i= t > performs better, and it seems that VirtualBox has a problem using AIO > to access zvols. > > But this didn;t show up for weeks because in the normal scheme of things > my virtual machines dont acccess the local dirve very much. It was only > when they started downloading patches that the crash happened. > > Solution is simple - disable AIO. All then goes back to being nice > and stable again. But it did take a while to find. > > Hope someone else finds the info usefull! > > -pete. > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"