From owner-freebsd-stable@FreeBSD.ORG Thu Jan 28 13:42:40 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 1771C106568B for ; Thu, 28 Jan 2010 13:42:40 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 5BF528FC20 for ; Thu, 28 Jan 2010 13:42:39 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id PAA19246; Thu, 28 Jan 2010 15:42:35 +0200 (EET) (envelope-from avg@icyb.net.ua) Message-ID: <4B61944B.8090602@icyb.net.ua> Date: Thu, 28 Jan 2010 15:42:35 +0200 From: Andriy Gapon User-Agent: Thunderbird 2.0.0.23 (X11/20091206) MIME-Version: 1.0 To: =?UTF-8?B?VG9tbWkgTMOkdHRp?= References: <4B6022C6.1090608@andric.com> In-Reply-To: X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: FreeBSD-STABLE Mailing List Subject: Re: immense delayed write to file system (ZFS and UFS2), performance issues 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: Thu, 28 Jan 2010 13:42:40 -0000 on 27/01/2010 22:26 Tommi Lätti said the following: > Seems that the performance is indeed atrocious. I recently (like 2 > days ago) had to rescue my zfs pool under opensolaris to spare disks. > The performance under OpenSol was what I was expecting, 70MB/s reading > and writing at the same time. > > Now that I'm restoring the stuff back under FreeBSD 8.0-p2 it seems > that first the array reads from the source disk and then stops reading > and decides to empty the buffer to the destination. There's usually a > 2 second pause and after that it goes back to reading. There seems to > be something really wrong with this, fbsd zfs implementation seems to > be unable to move data between 2 zfs pools writing and reading > simultaneously... > > I think I'll just boot back to opensol and do the transfers there. I've been seeing things like this too. Also, when copying between UFS and ZFS. -- Andriy Gapon