Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757935AbYAPCF5 (ORCPT ); Tue, 15 Jan 2008 21:05:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754407AbYAPCFs (ORCPT ); Tue, 15 Jan 2008 21:05:48 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:60139 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752074AbYAPCFr (ORCPT ); Tue, 15 Jan 2008 21:05:47 -0500 Date: Wed, 16 Jan 2008 11:05:09 +0900 From: KOSAKI Motohiro To: Paulo Marques Subject: Re: [RFC] mmaped copy too slow? Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Rik van Riel , Andrew Morton In-Reply-To: <478CAB25.30300@grupopie.com> References: <20080115100450.1180.KOSAKI.MOTOHIRO@jp.fujitsu.com> <478CAB25.30300@grupopie.com> Message-Id: <20080116110200.11B4.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.42 [ja] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 685 Lines: 26 Hi Paulo > One thing you could also try is to pass MAP_POPULATE to mmap so that the > page tables are filled in at the time of the mmap, avoiding a lot of > page faults later. > > Just my 2 cents, OK, I will test your idea and report about tomorrow. but I don't think page fault is major performance impact. may be, below 2 things too big - stupid page reclaim - large cache pollution by memcpy. Just my 2 cents :-p - kosaki -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/