From owner-freebsd-hackers@FreeBSD.ORG Wed Jun 27 02:21:12 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 35C99106564A for ; Wed, 27 Jun 2012 02:21:12 +0000 (UTC) (envelope-from rsimmons0@gmail.com) Received: from mail-lb0-f182.google.com (mail-lb0-f182.google.com [209.85.217.182]) by mx1.freebsd.org (Postfix) with ESMTP id A362E8FC12 for ; Wed, 27 Jun 2012 02:21:11 +0000 (UTC) Received: by lbon10 with SMTP id n10so1135754lbo.13 for ; Tue, 26 Jun 2012 19:21:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=aeRXwvzPF6CGRZpLO1tqgOiywZMyphhRBdJhFNT0t0I=; b=F0S6StaSodZG3MdfbaN0v/mGM4/TkYvo1zVEwGZL/vZYoyiT1qsTIIPf/0mRA8NW/z NXk/eNpP0S6+15nvFIJqTbQPFA5pgNT+BdDaspBIkIX9KN8meGER7/2NUpodBVNrsGAk DwWOE8KnYibvtF3mBmes6YllWoTjzbGz+iBWD4EGRg0rWYHJ/wXOiImtkQh++PotFt7n OZHhMQpzOJS5kv6xXiOAn/8qCF6oyjtMA7W7M6R1Y1ss5BGbinU9oQ3G7mHAQAWGDH0u 2Q7DsgsZEb3yr+kSvQJi9cd4xs1Vtt0uc0Gr6U/qmHrcuWeJw4PlXika7UQGBrhwlyPm Zqdw== MIME-Version: 1.0 Received: by 10.112.30.41 with SMTP id p9mr8894678lbh.26.1340763670267; Tue, 26 Jun 2012 19:21:10 -0700 (PDT) Received: by 10.112.107.170 with HTTP; Tue, 26 Jun 2012 19:21:10 -0700 (PDT) In-Reply-To: <20120627005428.298430@gmx.com> References: <20120627005428.298430@gmx.com> Date: Tue, 26 Jun 2012 22:21:10 -0400 Message-ID: From: Robert Simmons To: freebsd-hackers@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 Subject: Re: Freeze when running freebsd-update X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Jun 2012 02:21:12 -0000 On Tue, Jun 26, 2012 at 8:54 PM, Dieter BSD wrote: > Robert writes: >> 3) the box is responsive to hitting enter at the console (it produces >> another login: prompt) > > Getty is in memory and can run. > >> 5) if I try to login to the console, it lets me enter a username then >> locks up totally, it does not present me with a password: prompt. > > Login(1) is not in memory, and the kernel cannot read it from disk > for some reason. > > I can get this symptom by writing a large file to a disk on a > controller that FreeBSD doesn't support NCQ on. I assume there > is a logjam in the buffer cache. Something trivial like reading > login in from disk that would normally happen in well under a > second can take many minutes. > > Perhaps geli is causing a similar logjam? Does it hang forever or > is it just obscenely slow? If it truely hangs forever it is > probably something else. Is there disk activity after it hangs? > Can you try it without geli? systat -vmstat might provide a clue. I've done some more testing with forkbomb and if I bump the memory up to 512M I just get an error message on the console about the user exceeding maxproc and approaching the limit on PV entries. At that point I'm able to Ctrl-C and stop forkbomb: no freeze. I have a number of these instances, and I will reinstall one geli-free and see what happens. I will also reproduce the initial conditions and leave it for the night to see if it comes out of it. After a certain point there is no disk activity, and the uptime counter in the corner of top eventially freezes too, so I don't think it will come out of this, but we'll see.