From owner-freebsd-fs@FreeBSD.ORG Tue Aug 9 15:19:10 2011 Return-Path: Delivered-To: freebsd-fs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CC2591065676 for ; Tue, 9 Aug 2011 15:19:10 +0000 (UTC) (envelope-from jeremie@le-hen.org) Received: from smtp5-g21.free.fr (unknown [IPv6:2a01:e0c:1:1599::14]) by mx1.freebsd.org (Postfix) with ESMTP id 4CAAD8FC17 for ; Tue, 9 Aug 2011 15:19:08 +0000 (UTC) Received: from endor.tataz.chchile.org (unknown [82.233.239.98]) by smtp5-g21.free.fr (Postfix) with ESMTP id 2A257D480F9; Tue, 9 Aug 2011 17:19:02 +0200 (CEST) Received: from felucia.tataz.chchile.org (felucia.tataz.chchile.org [192.168.1.9]) by endor.tataz.chchile.org (Postfix) with ESMTP id 1483B3723C; Tue, 9 Aug 2011 15:19:02 +0000 (UTC) Received: by felucia.tataz.chchile.org (Postfix, from userid 1000) id 09A93A128A; Tue, 9 Aug 2011 15:19:02 +0000 (UTC) Date: Tue, 9 Aug 2011 17:19:02 +0200 From: Jeremie Le Hen To: Jeremy Chadwick Message-ID: <20110809151901.GA7877@felucia.tataz.chchile.org> References: <20110809131057.GA53580@felucia.tataz.chchile.org> <20110809135212.GA13334@icarus.home.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110809135212.GA13334@icarus.home.lan> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-fs@FreeBSD.org, Jeremie Le Hen Subject: Re: zfs mirror reads only on one disk X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Aug 2011 15:19:10 -0000 On Tue, Aug 09, 2011 at 06:52:12AM -0700, Jeremy Chadwick wrote: > > Performance was a little less than I estimated (I really don't care to > be honest), but this double-confirms that yes, reads do get split across > mirror members. By the way, I tried with the same disk (WD Caviar Black) (not the same size though) on Solaris 11: extended device statistics r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b device 1104.5 0.0 141371.6 0.0 0.0 0.9 0.0 0.9 1 95 c5t5d0 extended device statistics r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b device 1101.7 0.0 141014.0 0.0 0.0 0.9 0.0 0.9 1 95 c5t5d0 It can reach 140 MB/s! > Therefore I cannot explain what you're seeing. Maybe consider upgrading > to a newer RELENG_8 and ZFSv28 and see if things improve? I wish I had > a way to confirm this would fix your problem but I do not. Ok, I didn't know ZFS v28 was MFC'd to RELENG_8. By the way, I see you switched to the new ata(4) driver according to your device names. Is it painless to upgrade? I'll give it a try this evening hopefully. Thanks. Regards, -- Jeremie Le Hen Humans are born free and equal. But some are more equal than others. Coluche