From owner-freebsd-hackers@FreeBSD.ORG Wed Jun 27 17:51:22 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 670C910657E1 for ; Wed, 27 Jun 2012 17:51:22 +0000 (UTC) (envelope-from rsimmons0@gmail.com) Received: from mail-vc0-f182.google.com (mail-vc0-f182.google.com [209.85.220.182]) by mx1.freebsd.org (Postfix) with ESMTP id 211B78FC22 for ; Wed, 27 Jun 2012 17:51:22 +0000 (UTC) Received: by vcbfy7 with SMTP id fy7so1095749vcb.13 for ; Wed, 27 Jun 2012 10:51:21 -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=TxXYKMueRAHJA107jiZvdqKl0pzIqHgXfZTRzKpMEwo=; b=uefk+84Otmz4V0x6kPUaPpqhQ/5EP3UMZfXS83t+OjHFRz/TMfZyT+C+mTtW7JJLIy xBRg84ln3dru0QMhxg8uJ6q+n6cIapz4qh/wiWG+YTPmJ4scKEWykjll9Nv0T3yDXPqA Qp8z87+S4MR9IUeJbRITlndVJwFE2ZuKFCqJb+gT9gVX1A8hbU/2nLVTS8IoTFoTWslA 3E7qhzUg0zjipjbgAIhDWk0thnPR5MaOL+SQKw5qfxSf6YmEC8vAda8SbYL/7kX+LhI1 Bw65HDlHMbnz2JFJany1CAZ2NRimltfXtx1CmbRRGhBvN+VzjTUSNDswTeoE/t2IuY/s ApFA== MIME-Version: 1.0 Received: by 10.52.240.228 with SMTP id wd4mr12307114vdc.95.1340819481314; Wed, 27 Jun 2012 10:51:21 -0700 (PDT) Received: by 10.52.16.148 with HTTP; Wed, 27 Jun 2012 10:51:21 -0700 (PDT) In-Reply-To: <20120627063400.298430@gmx.com> References: <20120627063400.298430@gmx.com> Date: Wed, 27 Jun 2012 13:51:21 -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 17:51:22 -0000 On Wed, Jun 27, 2012 at 2:33 AM, 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. >> >> Well, it is geli. I'm unable to reproduce the freeze on the same >> exact system with everything else the same except for no geli. I'm >> going to move this thread over to geom, and continue it there. Thanks >> for your help! > > It occurs to me that it will need twice as much memory for disk i/o. > 1 buffer for encrypted and 1 for unencrypted. I know nothing about geli, > so I don't know if it uses the buffer cache for both, or what. > Could it be that the kernel isn't keeping enough memory free and > manages to paint itself into a corner and not have space to store > the unencrypted version of disk reads, and can't page/swap anything > out to make space because it doesn't have space to store the encrypted > version to write? I think that's probably about what is happening. I'm still waiting for an answer on the geom mailing list, but I will do some testing with increasing memory sizes and see where the problem stops occurring.