From owner-freebsd-fs@FreeBSD.ORG Mon Sep 6 12:35:15 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0E84A10656C7 for ; Mon, 6 Sep 2010 12:35:15 +0000 (UTC) (envelope-from prvs=186543ef20=killing@multiplay.co.uk) Received: from mail1.multiplay.co.uk (mail1.multiplay.co.uk [85.236.96.23]) by mx1.freebsd.org (Postfix) with ESMTP id 95AC78FC1A for ; Mon, 6 Sep 2010 12:35:14 +0000 (UTC) X-MDAV-Processed: mail1.multiplay.co.uk, Mon, 06 Sep 2010 13:35:09 +0100 X-Spam-Processed: mail1.multiplay.co.uk, Mon, 06 Sep 2010 13:35:09 +0100 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on mail1.multiplay.co.uk X-Spam-Level: X-Spam-Status: No, score=-5.0 required=6.0 tests=USER_IN_WHITELIST shortcircuit=ham autolearn=disabled version=3.2.5 Received: from r2d2 by mail1.multiplay.co.uk (MDaemon PRO v10.0.4) with ESMTP id md50011186407.msg for ; Mon, 06 Sep 2010 13:35:08 +0100 X-Authenticated-Sender: Killing@multiplay.co.uk X-MDRemoteIP: 188.220.16.49 X-Return-Path: prvs=186543ef20=killing@multiplay.co.uk X-Envelope-From: killing@multiplay.co.uk X-MDaemon-Deliver-To: freebsd-fs@freebsd.org Message-ID: <640F8FCE649448A4A8FF22214C993B10@multiplay.co.uk> From: "Steven Hartland" To: "Kostik Belousov" , "Andriy Gapon" References: <7EA7AD058C0143B2BF2471CC121C1687@multiplay.co.uk> <1F64110BFBD5468B8B26879A9D8C94EF@multiplay.co.uk> <4C83A214.1080204@DataIX.net> <06B9D23F202D4DB88D69B7C4507986B7@multiplay.co.uk> <4C842905.2080602@DataIX.net> <330B5DB2215F43899ABAEC2CF71C2EE0@multiplay.co.uk> <4C84C857.1070306@icyb.net.ua> <20100906110406.GC2396@deviant.kiev.zoral.com.ua> Date: Mon, 6 Sep 2010 13:35:07 +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 V6.00.2900.5931 Cc: freebsd-fs@freebsd.org, jhell Subject: Re: zfs very poor performance compared to ufs due to lack of cache? X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Sep 2010 12:35:15 -0000 On Mon, Sep 06, 2010 at 01:54:15PM +0300, Andriy Gapon wrote: >>> How does ufs deal with this, does it take inactive into account? Seems a bit >>> silly for inactive pages to prevent reuse for extended periods when the >>> memory could be better used as cache. >> >> Inactive pages are also a cache, just a different kind. > Not quite. Inactive pages may be dirty. Such pages cannot be freed or reused > without pageout. I assume my little test that allocates ram then frees it, which then returned to "free" rules this out in this case though? Regards Steve ================================================ This e.mail is private and confidential between Multiplay (UK) Ltd. and the person or entity to whom it is addressed. In the event of misdirection, the recipient is prohibited from using, copying, printing or otherwise disseminating it or any information contained in it. In the event of misdirection, illegible or incomplete transmission please telephone +44 845 868 1337 or return the E.mail to postmaster@multiplay.co.uk.