From owner-freebsd-geom@FreeBSD.ORG Fri Oct 17 17:04:06 2008 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 68C2D10656A1 for ; Fri, 17 Oct 2008 17:04:06 +0000 (UTC) (envelope-from bsd@fluffles.net) Received: from mail.fluffles.net (fluffles.net [80.69.95.190]) by mx1.freebsd.org (Postfix) with ESMTP id 2AE228FC15 for ; Fri, 17 Oct 2008 17:04:05 +0000 (UTC) (envelope-from bsd@fluffles.net) Received: from [10.10.0.2] (cust.95.160.adsl.cistron.nl [195.64.95.160]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: info@fluffles.net) by mail.fluffles.net (Postfix) with ESMTP id 0CFB7B29D6A; Fri, 17 Oct 2008 19:04:39 +0200 (CEST) Message-ID: <48F8C662.80602@fluffles.net> Date: Fri, 17 Oct 2008 19:07:46 +0200 From: "fluffles.net" User-Agent: Thunderbird 2.0.0.17 (X11/20080925) MIME-Version: 1.0 To: Giulio Ferro References: <48DE439C.4050505@zirakzigil.org> <48F1C760.1080902@zirakzigil.org> <48F22BDB.2040803@quip.cz> <48F3B35D.9060507@zirakzigil.org> In-Reply-To: <48F3B35D.9060507@zirakzigil.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Miroslav Lachman <000.fbsd@quip.cz>, freebsd-geom@freebsd.org Subject: Re: Problems with journal? X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Oct 2008 17:04:06 -0000 Giulio Ferro wrote: > Miroslav Lachman wrote: >> Giulio Ferro wrote: >>> Giulio Ferro wrote: >>> >>>> I'm experiencing very serious delay issues in 2 production servers. >>> >>> [...] >>> >>>> >>>> I hope any of you can help me look in the right direction, and >>>> point me to any further tests to try or tunable >>>> to set... >>>> >>>> Thanks in advance. >>>> >>> >>> I didn't receive any answer to this, so I'm guessing ufs journal >>> is abandoned or there is no interest in supporting it in production >>> environment. >>> Anyway I removed it from my servers and reverted to standard UFS, >>> so the problems disappeared. I also tried zfs (the only other >>> journaled >>> filesystem available on freebsd). I didn't experiences the hanging >>> behavior >>> I did with journaled ufs, but it's considerably slower than standard >>> ufs >>> (1/2 slower writes, 1/10 slower reads)... >> >> I am using gjournal on few production machines (not heavily IO >> loaded) without any hangs. > > I'm glad for you. Unfortunately, as I reported in my original message, if > the filesystem is cluttered enough even a simple "find" command can > very nearly freeze the system. Hi Giulio, Have you checked that your disks or array is not using PIO mode? Which uses hefty interrupts which will bring any system to its knees even on light I/O. For ata devices use atacontrol mode for scsi devices including hardware RAID lookup dmesg. I'm not sure if hardware RAID can use PIO, but any hybrid RAID / Fake RAID can. Also, during the journal commit, you may experience a delay. Could you provide some benchmarks like bonnie on the volume, without background I/O if possible. Not sure if any of this is related to your problem, though. Kind regards, Veronica