Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758845Ab0HEGNL (ORCPT ); Thu, 5 Aug 2010 02:13:11 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:37281 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757750Ab0HEGNJ (ORCPT ); Thu, 5 Aug 2010 02:13:09 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: LKML , linux-mm , Andrew Morton , Johannes Weiner , Mel Gorman , Wu Fengguang , Minchan Kim , Rik van Riel Subject: [PATCH 2/7] vmscan: synchronous lumpy reclaim don't call congestion_wait() Cc: kosaki.motohiro@jp.fujitsu.com In-Reply-To: <20100805150624.31B7.A69D9226@jp.fujitsu.com> References: <20100805150624.31B7.A69D9226@jp.fujitsu.com> Message-Id: <20100805151229.31BD.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Thu, 5 Aug 2010 15:13:03 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1371 Lines: 37 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 --- mm/vmscan.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index cf51d62..1cdc3db 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1341,7 +1341,6 @@ shrink_inactive_list(unsigned long nr_to_scan, struct zone *zone, /* Check if we should syncronously wait for writeback */ if (should_reclaim_stall(nr_taken, nr_reclaimed, priority, sc)) { - congestion_wait(BLK_RW_ASYNC, HZ/10); /* * The attempt at page out may have made some * of the pages active, mark them inactive again. -- 1.6.5.2 -- 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/