From owner-freebsd-fs@FreeBSD.ORG Sat Jul 6 05:10:35 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 15C9C954 for ; Sat, 6 Jul 2013 05:10:35 +0000 (UTC) (envelope-from daniel@digsys.bg) Received: from smtp-sofia.digsys.bg (smtp-sofia.digsys.bg [193.68.21.123]) by mx1.freebsd.org (Postfix) with ESMTP id 77B9017A1 for ; Sat, 6 Jul 2013 05:10:33 +0000 (UTC) Received: from [10.183.196.154] ([213.226.63.185]) (authenticated bits=0) by smtp-sofia.digsys.bg (8.14.6/8.14.6) with ESMTP id r665AUJ3070116 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Sat, 6 Jul 2013 08:10:31 +0300 (EEST) (envelope-from daniel@digsys.bg) References: <20130704000405.GA75529@icarus.home.lan> <20130704171637.GA94539@icarus.home.lan> <2A261BEA-4452-4F6A-8EFB-90A54D79CBB9@alumni.chalmers.se> <20130704191203.GA95642@icarus.home.lan> <43015E9015084CA6BAC6978F39D22E8B@multiplay.co.uk> <3CFB4564D8EB4A6A9BCE2AFCC5B6E400@multiplay.co.uk> <51D6A206.2020303@digsys.bg> <20130705145332.GA5449@icarus.home.lan> Mime-Version: 1.0 (1.0) In-Reply-To: <20130705145332.GA5449@icarus.home.lan> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Message-Id: <209EBC4A-45C6-4F94-87C3-9679B8A0691E@digsys.bg> X-Mailer: iPhone Mail (10B329) From: Daniel Kalchev Subject: Re: Slow resilvering with mirrored ZIL Date: Sat, 6 Jul 2013 08:10:29 +0300 To: Jeremy Chadwick 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: Sat, 06 Jul 2013 05:10:35 -0000 On 05.07.2013, at 17:53, Jeremy Chadwick wrote: > On Fri, Jul 05, 2013 at 01:37:58PM +0300, Daniel Kalchev wrote: >>=20 >> On 05.07.13 02:28, Steven Hartland wrote: >>>=20 >>>=20 >>> If anyone wants my current patches which add switch to 4k ashift >>> by default >>> as a sysctl + works with QUIRKS too, just let me know. >>>=20 >>> They are well tested, just we want more options before putting in >>> the tree. >>=20 >> Is it not easier to add this as an option to zpool create, instead >> of an sysctl? >>=20 >> That is, I believe we have two scenarios here: >>=20 >> 1. Having an sysctl that instructs ZFS to look at the FreeBSD quirks >> to decide what the ashift should be, instead of only querying the >> 'sectorsize' property of the storage. I believe we might not even >> need an sysctl here, just make it default to obey the quirks --- but >> sysctl for the interim period will not hurt (with the proper >> default). >=20 > I can expand on this one (specifically "relying on sectorsize of the > media"): no, this will not work reliably, for two reasons. =20 This is how ZFS works now. While I am we'll aware that most people use disk= s with all the quirks manufacturers put there, lets not forget ZFS was desig= ned for the enterprise environment, where "storage device" has much wider me= aning and "sector size" also varies wildly. Having said this and because FreeBSD actually goes via geom for disks now, f= iguring out the correct "sector size" is for geom to do. As it is now, perha= ps ZFS should be made to query the "stripe size" property of the geom provid= er and not the "sector size". A sysctl to that effect makes more sense to me= , will make things more automatic for most users. Daniel=