From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 16 Jan 2008 11:05:09 +0900 From: KOSAKI Motohiro Subject: Re: [RFC] mmaped copy too slow? 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 Sender: owner-linux-mm@kvack.org Return-Path: To: Paulo Marques Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Rik van Riel , Andrew Morton List-ID: 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org