Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760576Ab0HENzT (ORCPT ); Thu, 5 Aug 2010 09:55:19 -0400 Received: from mail-pw0-f46.google.com ([209.85.160.46]:48572 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754772Ab0HENzO (ORCPT ); Thu, 5 Aug 2010 09:55:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=TZdFVPGPoIkIcQsZqVrpG5npNrfRCgwj9lQq1ALtMhRLCIN0aNMYsq7GSmUROt7Gra o5WCNfvJZNYO2VAsp/YxZoAwxCSgPpsnxI91ro3kP69wEA7iZKugz8uvSG029oZWUFuc eLYeQ9dZAogQKirbG14WmJKl1HpsE1pUCYA90= Date: Thu, 5 Aug 2010 22:55:04 +0900 From: Minchan Kim To: KOSAKI Motohiro Cc: LKML , linux-mm , Andrew Morton , Johannes Weiner , Mel Gorman , Wu Fengguang , Rik van Riel Subject: Re: [PATCH 2/7] vmscan: synchronous lumpy reclaim don't call congestion_wait() Message-ID: <20100805135504.GA2985@barrios-desktop> References: <20100805150624.31B7.A69D9226@jp.fujitsu.com> <20100805151229.31BD.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100805151229.31BD.A69D9226@jp.fujitsu.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 975 Lines: 22 On Thu, Aug 05, 2010 at 03:13:03PM +0900, KOSAKI Motohiro wrote: > congestion_wait() mean "waiting quueue congestion is cleared". > That said, if the system have plenty dirty pages and flusher thread push > new request to IO queue conteniously, IO queue are not cleared > congestion status for long time. thus, congestion_wait(HZ/10) become > almostly equivalent schedule_timeout(HZ/10). > > However, synchronous lumpy reclaim donesn't need this > congestion_wait() at all. shrink_page_list(PAGEOUT_IO_SYNC) are > using wait_on_page_writeback() and it provide sufficient waiting. > > Signed-off-by: KOSAKI Motohiro Reviewed-by: Minchan Kim -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/