From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 209A26B01AF for ; Tue, 6 Jul 2010 07:13:44 -0400 (EDT) Received: from m4.gw.fujitsu.co.jp ([10.0.50.74]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o66BDfwt023850 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Tue, 6 Jul 2010 20:13:41 +0900 Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 3BE7145DE60 for ; Tue, 6 Jul 2010 20:13:41 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 1875345DE4D for ; Tue, 6 Jul 2010 20:13:41 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 021F91DB8037 for ; Tue, 6 Jul 2010 20:13:41 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 9B5711DB8040 for ; Tue, 6 Jul 2010 20:13:37 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH 12/14] vmscan: Do not writeback pages in direct reclaim In-Reply-To: <20100706101235.GE13780@csn.ul.ie> References: <20100706093529.CCD1.A69D9226@jp.fujitsu.com> <20100706101235.GE13780@csn.ul.ie> Message-Id: <20100706200310.CD06.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Tue, 6 Jul 2010 20:13:36 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Dave Chinner , Chris Mason , Nick Piggin , Rik van Riel , Johannes Weiner , Christoph Hellwig , KAMEZAWA Hiroyuki , Andrea Arcangeli List-ID: > On Tue, Jul 06, 2010 at 09:36:41AM +0900, KOSAKI Motohiro wrote: > > Hello, > > > > > Ok, that's reasonable as I'm still working on that patch. For example, the > > > patch disabled anonymous page writeback which is unnecessary as the stack > > > usage for anon writeback is less than file writeback. > > > > How do we examine swap-on-file? > > > > Anything in particular wrong with the following? > > /* > * For now, only kswapd can writeback filesystem pages as otherwise > * there is a stack overflow risk > */ > static inline bool reclaim_can_writeback(struct scan_control *sc, > struct page *page) > { > return !page_is_file_cache(page) || current_is_kswapd(); > } > > Even if it is a swapfile, I didn't spot a case where the filesystems > writepage would be called. Did I miss something? Hmm... Now, I doubt I don't understand your mention. Do you mean you intend to swtich task stack when every writepage? It seems a bit costly. but otherwise write-page for anon makes filesystem IO and stack-overflow. Can you please elaborate your plan? -- 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