From owner-freebsd-questions@FreeBSD.ORG Sat Aug 21 18:29:08 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 724071065698 for ; Sat, 21 Aug 2010 18:29:08 +0000 (UTC) (envelope-from stefreak@stefreak.de) Received: from mail.commail.org (vs1.stefreak.de [80.190.156.217]) by mx1.freebsd.org (Postfix) with ESMTP id 0793F8FC16 for ; Sat, 21 Aug 2010 18:29:07 +0000 (UTC) Received: from [192.168.178.29] (port-92-202-42-83.dynamic.qsc.de [92.202.42.83]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.commail.org (Postfix) with ESMTPSA id D1259533ED for ; Sat, 21 Aug 2010 20:29:06 +0200 (CEST) Message-ID: <4C701AF1.7030304@stefreak.de> Date: Sat, 21 Aug 2010 20:29:05 +0200 From: Steffen Neubauer User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.2.8) Gecko/20100802 Thunderbird/3.1.2 MIME-Version: 1.0 To: freebsd-questions@freebsd.org References: <4C701170.9080306@stefreak.de> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: IO fluctuation X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 Aug 2010 18:29:08 -0000 Hello Claudiu :) Sorry that I didn't answer these obvious questions in my first post. Am 21.08.2010 20:16, schrieb claudiu vasadi: > How did you setup your drives in ZFS ? stripe ? raidz1 .... Here is my zpool status output: # zpool status pool: tank state: ONLINE scrub: none requested config: NAME STATE READ WRITE CKSUM tank ONLINE 0 0 0 raidz1 ONLINE 0 0 0 gptid/7b91a9b4-ab05-11df-8c6e-001d7d004144 ONLINE 0 0 0 gptid/7cebaf7b-ab05-11df-8c6e-001d7d004144 ONLINE 0 0 0 gptid/7e43d7a2-ab05-11df-8c6e-001d7d004144 ONLINE 0 0 0 errors: No known data errors > what bsd version do you have and what platform ? # uname -a FreeBSD tank 8.1-RELEASE FreeBSD 8.1-RELEASE #0: Mon Jul 19 02:36:49 UTC 2010 root@mason.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64 > Do you see this big fluctuation when copying some big file like say and iso > or movie ? Both, on small filesystem access and when copying big files. When I'm listening to music with VLC over NFS it stalls regularly. When I'm working on the shell the commands block randomly for a certain time. But I get that fluctuation on raw device access, too, look: # dd if=/dev/ad0 of=/dev/zero bs=1M ^C0+0 records in 0+0 records out 0 bytes transferred in 9.848682 secs (0 bytes/sec) # dd if=/dev/ad0 of=/dev/zero bs=1M ^C1056+0 records in 1056+0 records out 1107296256 bytes transferred in 9.492375 secs (116651130 bytes/sec) So this is not a zfs problem. But I don't think it's the hardware, too - I used that mainboard before FreeBSD with no problems. And the WD EARS drives can't be the problem on raw device access, too, because I used bs=1M, that should be enough... This is really strange... Greetings, Steffen