From owner-freebsd-fs@FreeBSD.ORG Wed Jul 3 14:53:05 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 0CEDD185 for ; Wed, 3 Jul 2013 14:53:05 +0000 (UTC) (envelope-from feld@feld.me) Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by mx1.freebsd.org (Postfix) with ESMTP id D533910C8 for ; Wed, 3 Jul 2013 14:53:04 +0000 (UTC) Received: from compute4.internal (compute4.nyi.mail.srv.osa [10.202.2.44]) by gateway1.nyi.mail.srv.osa (Postfix) with ESMTP id DA85B211D2; Wed, 3 Jul 2013 10:53:03 -0400 (EDT) Received: from frontend2.nyi.mail.srv.osa ([10.202.2.161]) by compute4.internal (MEProxy); Wed, 03 Jul 2013 10:53:03 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=feld.me; h= content-type:to:cc:subject:references:date:mime-version :content-transfer-encoding:from:message-id:in-reply-to; s= mesmtp; bh=WO4IjV/IhYkEcIXFzzcDCjrotuw=; b=OpnANfXPL208eEg+hQPmH LU+aAc1I2k52am/293acCy/EWUebzZ5kB2hHbZ5Zlbexj2MVgexdfVCK7BODhoMT bpW8IKJAYKjuuKDTeikPiPkcbUPGeglVSCLWmx7xCyDEnNxRkDHJ3w5yxf3iAcAv 37qM1PcRXGBuMOXmyS5fpg= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=content-type:to:cc:subject:references :date:mime-version:content-transfer-encoding:from:message-id :in-reply-to; s=smtpout; bh=WO4IjV/IhYkEcIXFzzcDCjrotuw=; b=pzfI E2V98nJEUKfhBKLNJrYfy7NFCrb92o56bgTWykbJSmWO2j5rNqI4qMU2/Xpf0WxO 2DW1r9P/Ib5bcdOej9RRfpS1BX34gkDqpEk/P9rxSA8KNgoNi561Wu5N6CQSopYK pcni4FAmOxUcjJEg+GxmcpGc7+fvMAlwDPrFUug= X-Sasl-enc: EMpGqfnJf7Qp6itTWPgR5bdAtlv3V5n2oTXNTtNxl9AL 1372863183 Received: from tech304.office.supranet.net (unknown [66.170.8.18]) by mail.messagingengine.com (Postfix) with ESMTPA id 89B4D680252; Wed, 3 Jul 2013 10:53:03 -0400 (EDT) Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes To: mxb , "Daniel Kalchev" Subject: Re: Slow resilvering with mirrored ZIL References: <51D42107.1050107@digsys.bg> <2EF46A8C-6908-4160-BF99-EC610B3EA771@alumni.chalmers.se> <51D437E2.4060101@digsys.bg> Date: Wed, 03 Jul 2013 09:53:03 -0500 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: "Mark Felder" Message-ID: In-Reply-To: <51D437E2.4060101@digsys.bg> User-Agent: Opera Mail/12.15 (FreeBSD) Cc: freebsd-fs@freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Jul 2013 14:53:05 -0000 On Wed, 03 Jul 2013 09:40:34 -0500, Daniel Kalchev wrote: > > What is happening during resilver is reading from the other drives in > the vdev and writing to the new drive. You mention four drives so I > assume this is an raidz? Is it possible that the old drives and the > zpool vdev(s) are 512byte sector size and the new drive is 4k sector > size? If so, you might experience severe slowdown. The only way to fix > this situation is to recreate the zpool -- copy data out of the pool, > create the pool with 4k alignment for vdevs and copy data back. This might be what he's experiencing -- I ran into this recently when I knowingly put a 4K drive into a server that used 512b sectors in the zpool. It was an emergency as we ran out of 512b 2TB spares. As soon as we got a proper spare I did replace the drive and performance went back to normal and the resilver was extremely fast too.