From owner-freebsd-fs@FreeBSD.ORG Fri Feb 7 22:50:39 2014 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 38659756 for ; Fri, 7 Feb 2014 22:50:39 +0000 (UTC) Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 057541204 for ; Fri, 7 Feb 2014 22:50:38 +0000 (UTC) Received: from compute2.internal (compute2.nyi.mail.srv.osa [10.202.2.42]) by gateway1.nyi.mail.srv.osa (Postfix) with ESMTP id 9F80D20EA8; Fri, 7 Feb 2014 17:50:37 -0500 (EST) Received: from web3 ([10.202.2.213]) by compute2.internal (MEProxy); Fri, 07 Feb 2014 17:50:37 -0500 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=message-id:from:to:cc:mime-version :content-transfer-encoding:content-type:subject:date:in-reply-to :references; s=smtpout; bh=z4SdapWDYz5Cmge4b5pjfiLGQUU=; b=YiEgj 4YHLDZItjw3YN13/G2PycYqomQh8XH6GUVWSq14dyJCmyLWnt5FOnLr9xFeMIBZi UFq9Fsdk8kIj8yKbFE0btgcQ80Kabr9P4m9W0oKS0s6RFKlxI5NCLCBfOb7NXFwR +6fDVXMnfFaWyGLVn9/gUEBwn8IfymwWePDpII= Received: by web3.nyi.mail.srv.osa (Postfix, from userid 99) id 4F56210E639; Fri, 7 Feb 2014 17:50:37 -0500 (EST) Message-Id: <1391813437.29897.80736933.1F6388D0@webmail.messagingengine.com> X-Sasl-Enc: 1Y2PeOy6LBENceYS7uCCqy3jEjgO0UWAjS6K4ftThVz6 1391813437 From: Mark Felder To: Warren Block MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain X-Mailer: MessagingEngine.com Webmail Interface - ajax-e72899be Subject: Re: Using the *real* sector/block size of a mass storage device for ZFS Date: Fri, 07 Feb 2014 16:50:37 -0600 In-Reply-To: References: <1487AF77-7731-4AF8-8E44-FF814BB8A717@ebureau.com> <1391808195.4799.80708189.5CAD8A4E@webmail.messagingengine.com> Cc: freebsd-fs@freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Feb 2014 22:50:39 -0000 On Fri, Feb 7, 2014, at 16:19, Warren Block wrote: > On Fri, 7 Feb 2014, Mark Felder wrote: > > > On Fri, Feb 7, 2014, at 14:44, Dustin Wenz wrote: > >> We have been upgrading systems from FreeBSD 9.2 to 10.0-RELEASE, and I'm > >> noticing that all of my zpools now show this status: "One or more devices > >> are configured to use a non-native block size. Expect reduced > >> performance." Specifically, each disk reports: "block size: 512B > >> configured, 4096B native". > >> > >> I've checked these disks with diskinfo and smartctl, and they report a > >> sector size of 512B. I understand that modern disks often use larger > >> sectors due to addressing limits, but I'm unsure how ZFS can disagree > >> with these other tools. > >> > >> In any case, it looks like I will need to rebuild every zpool. There are > >> many thousands of disks involved and the process will take months (if not > >> years). How can I be I sure that this is done correctly this time? Will > >> ZFS automatically choose the correct block size, assuming that it's > >> really capable of this? > >> > >> In the meantime, how can I turn off that warning message on all of my > >> disks? "zpool status -x" is almost worthless due to the extreme number of > >> errors reported. > >> > > > > ZFS is doing the right thing by telling you that you should expect > > degraded performance. The best way to fix this is to use the gnop method > > when you build your zpools: > > > > gnop create -S 4096 /dev/da0 > > gnop create -S 4096 /dev/da1 > > zpool create data mirror /dev/da0.nop /dev/da1.nop > > > > Next reboot or import of the zpool will use the regular device names > > with the correct ashift for 4K drives. > > But remember that this does not fix alignment, and if the partitions are > not aligned with 4K blocks, at least write performance will suffer. > I often use raw devices ever since ZFS has had the ability to tolerate slight differences in disk sizes.