From owner-freebsd-current@FreeBSD.ORG Mon Dec 19 16:36:51 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3C9A41065679; Mon, 19 Dec 2011 16:36:51 +0000 (UTC) (envelope-from mike@reifenberger.com) Received: from mail-out.m-online.net (mail-out.m-online.net [IPv6:2001:a60:0:32:0:1:25:1]) by mx1.freebsd.org (Postfix) with ESMTP id 9811E8FC22; Mon, 19 Dec 2011 16:36:50 +0000 (UTC) Received: from frontend1.mail.m-online.net (frontend1.mail.intern.m-online.net [192.168.8.180]) by mail-out.m-online.net (Postfix) with ESMTP id 2D8411802C66; Mon, 19 Dec 2011 17:36:49 +0100 (CET) Received: from localhost (dynscan1.mnet-online.de [192.168.8.164]) by mail.m-online.net (Postfix) with ESMTP id 43BAF1C00124; Mon, 19 Dec 2011 17:36:49 +0100 (CET) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.180]) by localhost (dynscan1.mail.m-online.net [192.168.8.164]) (amavisd-new, port 10024) with ESMTP id jHAlzghSZ0Kz; Mon, 19 Dec 2011 17:36:45 +0100 (CET) Received: from mail.reifenberger.com (ppp-93-104-61-230.dynamic.mnet-online.de [93.104.61.230]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPS; Mon, 19 Dec 2011 17:36:44 +0100 (CET) Received: by mail.reifenberger.com (Postfix, from userid 1001) id 1A71C24B83; Mon, 19 Dec 2011 17:36:43 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by mail.reifenberger.com (Postfix) with ESMTP id 106D724B82; Mon, 19 Dec 2011 17:36:43 +0100 (CET) Date: Mon, 19 Dec 2011 17:36:42 +0100 (CET) From: Michael Reifenberger To: Stefan Esser In-Reply-To: <4EEF488E.1030904@freebsd.org> Message-ID: References: <4EEF488E.1030904@freebsd.org> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: FreeBSD Current Subject: Re: Uneven load on drives in ZFS RAIDZ1 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Dec 2011 16:36:51 -0000 Hi, a quick test using `dd if=/dev/zero of=/test ...` shows: dT: 10.004s w: 10.000s filter: ^a?da?.$ L(q) ops/s r/s kBps ms/r w/s kBps ms/w %busy Name 0 378 0 0 12.5 376 36414 11.9 60.6| ada0 0 380 0 0 12.2 378 36501 11.8 60.0| ada1 0 382 0 0 7.7 380 36847 11.6 59.2| ada2 0 375 0 0 7.4 374 36164 9.6 51.3| ada3 0 377 0 1 10.2 375 36325 10.1 53.3| ada4 10 391 0 0 39.3 389 38064 15.7 80.2| ada5 Seems to be sufficiently equally distributed for a life system... zpool status shows: ... NAME STATE READ WRITE CKSUM boot ONLINE 0 0 0 raidz1-0 ONLINE 0 0 0 ada0p3 ONLINE 0 0 0 ada1p3 ONLINE 0 0 0 ada2p3 ONLINE 0 0 0 ada3p3 ONLINE 0 0 0 ada4p3 ONLINE 0 0 0 ada5p3 ONLINE 0 0 0 ... The only cases I've seen (and expected to see) unequal load distributions on ZFS was after extending a nearly full four disk mirror pool by additional two disks. Bye/2 --- Michael Reifenberger Michael@Reifenberger.com http://www.Reifenberger.com