From owner-freebsd-stable@FreeBSD.ORG Fri Nov 26 19:14:48 2010 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 828201065674; Fri, 26 Nov 2010 19:14:48 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id DCB818FC13; Fri, 26 Nov 2010 19:14:47 +0000 (UTC) Received: by fxm16 with SMTP id 16so1002795fxm.13 for ; Fri, 26 Nov 2010 11:14:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=7LPL9i5k/7pDkMwMtxN3/qsveoP7Ykgt2uwpYo5/zCg=; b=gv1AoKgOUAdy/9pFP7gMFH+JTaEHS6vDK12+z5LIupUS/IoeUqrgeo/dcTfRnwyE7e QHzoEhlkka/z4ytRttH9/NzPwWqZVdPUu3ZbQ6ZdaFK4jev0AqKNLsx3NU0Jc7CC0Y9y /d68NtFxQyWiNhQmbbaoYeU1CqwlZtzvcRqZk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=dLWXFVQyZLT487yPFT4SVriWi8oJvIjLqwC69HQEtub+BmdnHz0QIiNupJbCgpsNnD 06lOo5ha7bCPmH0lDIeabJB7ePDwmwu02d9Rqd2IlKebjJhGW2uPjR7TD1YQS/8Sjbly 9Z4H4Jtnw9rjZfBaEENPdhvxdZtTaBnd3RJ6g= MIME-Version: 1.0 Received: by 10.223.78.136 with SMTP id l8mr2452511fak.82.1290798886685; Fri, 26 Nov 2010 11:14:46 -0800 (PST) Received: by 10.223.121.138 with HTTP; Fri, 26 Nov 2010 11:14:46 -0800 (PST) In-Reply-To: <4CEFC534.2070904@DataIX.net> References: <4CEFB8F7.4080002@freebsd.org> <4CEFC534.2070904@DataIX.net> Date: Fri, 26 Nov 2010 13:14:46 -0600 Message-ID: From: Adam Vande More To: jhell Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org, Andriy Gapon Subject: Re: More IO identification problems 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: Fri, 26 Nov 2010 19:14:48 -0000 On Fri, Nov 26, 2010 at 8:33 AM, jhell wrote: > > Perhaps it's some external component? > > E.g. hald is known to perform some disk/media checks every two seconds. > > > > As well syslod will also cause sync to happen prematurely when something > goes to log. > > syslog.conf(5): > *** > To ensure that kernel messages are written to disk promptly, > syslog.conf calls fsync(2) after writing messages from the kernel. > Other messages are not synced explicitly. You may prefix a pathname > with the minus sign, ``-'', to forego syncing the specified file > after every kernel message. Note that you might lose information if > the system crashes immediately following a write attempt. Neverthe- > less, using the ``-'' option may improve performance, especially if > the kernel is logging many messages. > *** > > This is obviously the old way of ensuring logs are written to disk > before crash but now ZFS is handled differently. Check to see if adding > '-' to your syslog entries relieves that problem as ZFS will do the > right thing to ensure your data is written to disk. > Thanks, avg and jhell. hald was indeed the culprit, and a "hal-disable-polling --device /dev/cd0" has restored my sanity. I never liked the cd notifications anyway. -- Adam Vande More