From owner-freebsd-fs@FreeBSD.ORG Sat Jun 8 18:54:05 2013 Return-Path: Delivered-To: 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 EDEE15D3 for ; Sat, 8 Jun 2013 18:54:05 +0000 (UTC) (envelope-from smh@freebsd.org) Received: from smtp1.multiplay.co.uk (smtp1.multiplay.co.uk [85.236.96.35]) by mx1.freebsd.org (Postfix) with ESMTP id B931E103A for ; Sat, 8 Jun 2013 18:54:05 +0000 (UTC) Received: by smtp1.multiplay.co.uk (Postfix, from userid 65534) id 35E6B20E7088A; Sat, 8 Jun 2013 18:54:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.multiplay.co.uk X-Spam-Level: X-Spam-Status: No, score=-1.4 required=8.0 tests=ALL_TRUSTED,AWL,BAYES_00, STOX_REPLY_TYPE,STOX_REPLY_TYPE_WITHOUT_QUOTES autolearn=no version=3.3.1 Received: from r2d2 (82-69-141-170.dsl.in-addr.zen.co.uk [82.69.141.170]) by smtp1.multiplay.co.uk (Postfix) with ESMTPA id 987B820E70847 for ; Sat, 8 Jun 2013 18:54:03 +0000 (UTC) Message-ID: <16FEF774EE8E4100AD2CAEC65276A49D@multiplay.co.uk> From: "Steven Hartland" To: Subject: Changing the default for ZFS atime to off? Date: Sat, 8 Jun 2013 19:54:04 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 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, 08 Jun 2013 18:54:06 -0000 One of the first changes we make here when installing machines here to changing atime=off on all ZFS pool roots. I know there are a few apps which can rely on atime updates such as qmail and possibly postfix, but those seem like special cases for which admins should enable atime instead of the other way round. This is going to of particular interest for flash based storage which should avoid unnessacary writes to reduce wear, but it will also help improve performance in general. So what do people think is it worth considering changing the default from atime=on to atime=off moving forward? If so what about UFS, same change? Regards Steve