From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 09EF66B0093 for ; Wed, 8 Dec 2010 03:16:02 -0500 (EST) Received: by iwn1 with SMTP id 1so1309444iwn.37 for ; Wed, 08 Dec 2010 00:16:01 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20101208170504.1750.A69D9226@jp.fujitsu.com> References: <0724024711222476a0c8deadb5b366265b8e5824.1291568905.git.minchan.kim@gmail.com> <20101208170504.1750.A69D9226@jp.fujitsu.com> Date: Wed, 8 Dec 2010 17:16:01 +0900 Message-ID: Subject: Re: [PATCH v4 4/7] Reclaim invalidated page ASAP From: Minchan Kim Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: Andrew Morton , Rik van Riel , linux-mm , LKML , Wu Fengguang , Johannes Weiner , Nick Piggin List-ID: On Wed, Dec 8, 2010 at 5:04 PM, KOSAKI Motohiro wrote: >> invalidate_mapping_pages is very big hint to reclaimer. >> It means user doesn't want to use the page any more. >> So in order to prevent working set page eviction, this patch >> move the page into tail of inactive list by PG_reclaim. >> >> Please, remember that pages in inactive list are working set >> as well as active list. If we don't move pages into inactive list's >> tail, pages near by tail of inactive list can be evicted although >> we have a big clue about useless pages. It's totally bad. >> >> Now PG_readahead/PG_reclaim is shared. >> fe3cba17 added ClearPageReclaim into clear_page_dirty_for_io for >> preventing fast reclaiming readahead marker page. >> >> In this series, PG_reclaim is used by invalidated page, too. >> If VM find the page is invalidated and it's dirty, it sets PG_reclaim >> to reclaim asap. Then, when the dirty page will be writeback, >> clear_page_dirty_for_io will clear PG_reclaim unconditionally. >> It disturbs this serie's goal. >> >> I think it's okay to clear PG_readahead when the page is dirty, not >> writeback time. So this patch moves ClearPageReadahead. >> >> Signed-off-by: Minchan Kim >> Acked-by: Rik van Riel >> Acked-by: Mel Gorman >> Cc: Wu Fengguang >> Cc: KOSAKI Motohiro >> Cc: Johannes Weiner >> Cc: Nick Piggin > > Until anyone should data, I will not ack this. This patch increase > VM state, but benefit is doubious. Make sense to me. If Ben is busy, I will measure it and send the result. Thanks! -- Kind regards, Minchan Kim -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org