From owner-freebsd-stable@FreeBSD.ORG Sun Feb 12 00:54:39 2012 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 9550B106564A for ; Sun, 12 Feb 2012 00:54:39 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-wi0-f182.google.com (mail-wi0-f182.google.com [209.85.212.182]) by mx1.freebsd.org (Postfix) with ESMTP id 208D48FC0C for ; Sun, 12 Feb 2012 00:54:38 +0000 (UTC) Received: by wibhn14 with SMTP id hn14so4251533wib.13 for ; Sat, 11 Feb 2012 16:54:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=VALDAJEW2mflsazkAIj7v+wWJIXIVJnjxyz/QzeH/ss=; b=OcSJtzka6DE+ifYwG7bk4ye7pwFLNe/Zk1l4sLGScn0A+5TehtsyoL/oqJns/nlYMA 9lLAYdBXhvPLdecUsY3bGfLau1pE2Ye2nlsRmb8a82e66R1+b43quoN3js+XEV9R30ay V0HxC4zIT+4MmTGvJP0JvE3QamkgLQ/kg4vvY= MIME-Version: 1.0 Received: by 10.216.133.205 with SMTP id q55mr2840656wei.6.1329008077813; Sat, 11 Feb 2012 16:54:37 -0800 (PST) Sender: adrian.chadd@gmail.com Received: by 10.216.175.136 with HTTP; Sat, 11 Feb 2012 16:54:37 -0800 (PST) In-Reply-To: <4F27C7C7.3060807@os2.kiev.ua> References: <4F215A99.8020003@os2.kiev.ua> <4F27C04F.7020400@omnilan.de> <4F27C7C7.3060807@os2.kiev.ua> Date: Sat, 11 Feb 2012 16:54:37 -0800 X-Google-Sender-Auth: kBcra9gatvZ4Dhjy-Ut49A4NjfY Message-ID: From: Adrian Chadd To: Alex Samorukov Content-Type: text/plain; charset=ISO-8859-1 Cc: Harald Schmalzbauer , freebsd-stable@freebsd.org Subject: Re: disk devices speed is ugly 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: Sun, 12 Feb 2012 00:54:39 -0000 Hi, What about the disk access is unaligned? Do you mean not sector aligned? or? This is a common problem people face doing disk IO analysis. The whole point about not allowing unaligned access is to make the disk IO path cleaner. It does mean that the filesystem code (and GEOM modules involved) need to be smarter. If the filesystem is doing ridiculously unaligned access then it likely should be fixed. Adrian