From owner-freebsd-arch@FreeBSD.ORG Wed Jan 6 11:12:51 2010 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0B87C1065694; Wed, 6 Jan 2010 11:12:51 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-ew0-f226.google.com (mail-ew0-f226.google.com [209.85.219.226]) by mx1.freebsd.org (Postfix) with ESMTP id 656F48FC18; Wed, 6 Jan 2010 11:12:50 +0000 (UTC) Received: by ewy26 with SMTP id 26so15289457ewy.3 for ; Wed, 06 Jan 2010 03:12:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=XzhHi7FS7TpYLV2ytum6yNcoYx7NCFKfaa+VoCpDqeU=; b=fKnqb5AxiWzgInFcOEP9vFCPeNNtBp3cvvbxoFONRsS63s85QRQqnrFcAcgUahm0Ps A6CZe5CmxY4qRU++x6P+hnggDD0yfKxa02hDM+ZcXsbI5j4SU/AerBE59H2m6kUgJ6mf JQyvBRoyzpvxQ/5MZ8l7+0AAB1fLekeW2nHqg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=pNd7NsOzauOtgrNu3eVT1111xXfbhJtnZkfnnyPI87kSv2/Zv8ZWlToirEo3hzevlN AJ/YTKYluwAjvCQHq2KK/NxbliUns5lrZu91CbEJCtQAk9CqrhzwXOT5yb1nt0iyEUaS lILKn3J51vL2Nj1c/mHdWo/D4I+wHTAZ5UgP0= Received: by 10.213.45.147 with SMTP id e19mr17541249ebf.17.1262776364839; Wed, 06 Jan 2010 03:12:44 -0800 (PST) Received: from mavbook.mavhome.dp.ua ([72.14.240.162]) by mx.google.com with ESMTPS id 10sm33944970eyd.37.2010.01.06.03.12.43 (version=SSLv3 cipher=RC4-MD5); Wed, 06 Jan 2010 03:12:44 -0800 (PST) Sender: Alexander Motin Message-ID: <4B44702B.9090503@FreeBSD.org> Date: Wed, 06 Jan 2010 13:12:43 +0200 From: Alexander Motin User-Agent: Thunderbird 2.0.0.23 (X11/20091212) MIME-Version: 1.0 To: =?UTF-8?B?RGFnLUVybGluZyBTbcO4cmdyYXY=?= References: <65036.1262386032@critter.freebsd.dk> <201001020101.16450.pieter@degoeje.nl> <86637fjypj.fsf@ds4.des.no> In-Reply-To: <86637fjypj.fsf@ds4.des.no> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Miroslav Lachman <000.fbsd@quip.cz>, Thomas Backman , Poul-Henning Kamp , freebsd-current@freebsd.org, freebsd-arch@freebsd.org, Pieter de Goeje Subject: Re: File system blocks alignment X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Jan 2010 11:12:51 -0000 Dag-Erling Smørgrav wrote: > Pieter de Goeje writes: >> Poul-Henning Kamp writes: >>> Ideally, newfs/UFS should do a quick test to look for any obvious >>> boundaries, and DTRT, a nice little task for somebody :-) >> A search for the offset for which newfs (or a simpler test) runs >> fastest? Interesting idea :-) > > Or just default to 4 kB or even 8 kB, which has zero performance impact > (either way) for disks with 512 B sectors. AFAIK it is what latest Windows'es do, just with bigger value. While it is usually good, I am not sure it is a perfect solution. These WDC HDDs with installed "XP compatibility" jumper artificially shift addresses, adding some offset between logical and physical sectors to fit legacy 63 sectors partition offset. Such case should be detected and handled. The only problem is that these drives doesn't report this info now. :( -- Alexander Motin