From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 8241E6B024D for ; Wed, 21 Jul 2010 20:02:24 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o6M02Mvd015845 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Thu, 22 Jul 2010 09:02:22 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id D698945DE54 for ; Thu, 22 Jul 2010 09:02:21 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 9D37E45DE50 for ; Thu, 22 Jul 2010 09:02:21 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 6BA931DB805D for ; Thu, 22 Jul 2010 09:02:21 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 1658C1DB8055 for ; Thu, 22 Jul 2010 09:02:21 +0900 (JST) Date: Thu, 22 Jul 2010 08:57:34 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 4/8] vmscan: Do not writeback filesystem pages in direct reclaim Message-Id: <20100722085734.ff252542.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100721142710.GZ13117@csn.ul.ie> References: <1279545090-19169-1-git-send-email-mel@csn.ul.ie> <1279545090-19169-5-git-send-email-mel@csn.ul.ie> <20100719221420.GA16031@cmpxchg.org> <20100720134555.GU13117@csn.ul.ie> <20100720220218.GE16031@cmpxchg.org> <20100721115250.GX13117@csn.ul.ie> <20100721210111.06dda351.kamezawa.hiroyu@jp.fujitsu.com> <20100721142710.GZ13117@csn.ul.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Johannes Weiner , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Rik van Riel , Christoph Hellwig , Wu Fengguang , KOSAKI Motohiro , Andrew Morton , Andrea Arcangeli List-ID: On Wed, 21 Jul 2010 15:27:10 +0100 Mel Gorman wrote: > On Wed, Jul 21, 2010 at 09:01:11PM +0900, KAMEZAWA Hiroyuki wrote: > > But, hmm, memcg will have to select to enter this rounine based on > > the result of 1st memory reclaim. > > > > It has the option of igoring pages being dirtied but I worry that the > container could be filled with dirty pages waiting for flushers to do > something. I'll prepare dirty_ratio for memcg. It's not easy but requested by I/O cgroup guys, too... > > > > > > > - /* > > > - * The attempt at page out may have made some > > > - * of the pages active, mark them inactive again. > > > - */ > > > - nr_active = clear_active_flags(&page_list, NULL); > > > - count_vm_events(PGDEACTIVATE, nr_active); > > > + while (nr_reclaimed < nr_taken && nr_dirty && dirty_retry--) { > > > + wakeup_flusher_threads(laptop_mode ? 0 : nr_dirty); > > > + congestion_wait(BLK_RW_ASYNC, HZ/10); > > > > > > > Congestion wait is required ?? Where the congestion happens ? > > I'm sorry you already have some other trick in other patch. > > > > It's to wait for the IO to occur. > 1 tick penalty seems too large. I hope we can have some waitqueue in future. > > > - nr_reclaimed += shrink_page_list(&page_list, sc, PAGEOUT_IO_SYNC); > > > + /* > > > + * The attempt at page out may have made some > > > + * of the pages active, mark them inactive again. > > > + */ > > > + nr_active = clear_active_flags(&page_list, NULL); > > > + count_vm_events(PGDEACTIVATE, nr_active); > > > + > > > + nr_reclaimed += shrink_page_list(&page_list, sc, > > > + PAGEOUT_IO_SYNC, &nr_dirty); > > > + } > > > > Just a question. This PAGEOUT_IO_SYNC has some meanings ? > > > > Yes, in pageout it will wait on pages currently being written back to be > cleaned before trying to reclaim them. > Hmm. IIUC, this routine is called only when !current_is_kswapd() and pageout is done only whne current_is_kswapd(). So, this seems .... Wrong ? Thanks, -Kame -- 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