From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 68063900001 for ; Fri, 29 Apr 2011 11:25:45 -0400 (EDT) Received: by qwa26 with SMTP id 26so2620778qwa.14 for ; Fri, 29 Apr 2011 08:25:42 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20110428105027.GT4658@suse.de> References: <2b79bbf9ddceb73624f49bbe9477126147d875fd.1303833417.git.minchan.kim@gmail.com> <20110428105027.GT4658@suse.de> Date: Sat, 30 Apr 2011 00:25:41 +0900 Message-ID: Subject: Re: [RFC 5/8] compaction: remove active list counting From: Minchan Kim Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , linux-mm , LKML , Christoph Lameter , Johannes Weiner , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Rik van Riel , Andrea Arcangeli On Thu, Apr 28, 2011 at 7:50 PM, Mel Gorman wrote: > On Wed, Apr 27, 2011 at 01:25:22AM +0900, Minchan Kim wrote: >> acct_isolated of compaction uses page_lru_base_type which returns only >> base type of LRU list so it never returns LRU_ACTIVE_ANON or LRU_ACTIVE_FILE. >> So it's pointless to add lru[LRU_ACTIVE_[ANON|FILE]] to get sum. >> >> Cc: KOSAKI Motohiro >> Cc: Mel Gorman >> Cc: Rik van Riel >> Cc: Andrea Arcangeli >> Signed-off-by: Minchan Kim > > hmm, isolate_migratepages() is doing a linear scan of PFNs and is > calling __isolate_lru_page(..ISOLATE_BOTH..). Using page_lru_base_type > happens to work because we're only interested in the number of isolated > pages and your patch still covers that. Using page_lru might be more > accurate in terms of accountancy but does not seem necessary. True. > > Adding a comment explaining why we account for it as inactive and why > that's ok would be nice although I admit this is something I should have > done when acct_isolated() was introduced. When Kame pointed out comment, I wanted to avoid unnecessary comment so decided changing it with page_lru although it adds overhead a little bit. But Hannes, you and maybe Kame don't want it. I don't mind adding comment. Okay. fix it in next version. 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 internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org