From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753806AbZESGxk (ORCPT ); Tue, 19 May 2009 02:53:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753260AbZESGxd (ORCPT ); Tue, 19 May 2009 02:53:33 -0400 Received: from mga14.intel.com ([143.182.124.37]:42947 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753237AbZESGxc (ORCPT ); Tue, 19 May 2009 02:53:32 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.41,213,1241420400"; d="scan'208";a="144363480" Date: Tue, 19 May 2009 14:27:58 +0800 From: Wu Fengguang To: KOSAKI Motohiro Cc: Christoph Lameter , Andrew Morton , LKML , Elladan , Nick Piggin , Johannes Weiner , Peter Zijlstra , Rik van Riel , "tytso@mit.edu" , "linux-mm@kvack.org" , "minchan.kim@gmail.com" Subject: Re: [PATCH 2/3] vmscan: make mapped executable pages the first class citizen Message-ID: <20090519062757.GA9639@localhost> References: <20090519032759.GA7608@localhost> <20090519133422.4ECC.A69D9226@jp.fujitsu.com> <20090519050932.GB8769@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090519050932.GB8769@localhost> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 19, 2009 at 01:09:32PM +0800, Wu Fengguang wrote: > On Tue, May 19, 2009 at 12:41:38PM +0800, KOSAKI Motohiro wrote: > Note that I was creating the sparse file in btrfs, which happens to be > very slow in sparse file reading: > > 151.194384MB/s 284.198252s 100001x 450560b --load pattern-hot-10 --play /b/sparse > > In that case, the inactive list is rotated at the speed of 250MB/s, > so a full scan of which takes about 3.5 seconds, while a full scan > of active file list takes about 77 seconds. Hi KOSAKI: you can limit the read speed with iotrace.rb's "--think-time" option, or to read the sparse file over network. Thanks, Fengguang