Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756248Ab0FNU6L (ORCPT ); Mon, 14 Jun 2010 16:58:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23698 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755842Ab0FNU6I (ORCPT ); Mon, 14 Jun 2010 16:58:08 -0400 Subject: Re: [PATCH 03/12] tracing, vmscan: Add trace event when a page is written From: Larry Woodman To: Mel Gorman Cc: 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 , Andrew Morton In-Reply-To: <1276514273-27693-4-git-send-email-mel@csn.ul.ie> References: <1276514273-27693-1-git-send-email-mel@csn.ul.ie> <1276514273-27693-4-git-send-email-mel@csn.ul.ie> Content-Type: text/plain Date: Mon, 14 Jun 2010 17:02:51 -0400 Message-Id: <1276549371.8736.105.camel@dhcp-100-19-198.bos.redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 759 Lines: 17 On Mon, 2010-06-14 at 12:17 +0100, Mel Gorman wrote: > This patch adds a trace event for when page reclaim queues a page for IO and > records whether it is synchronous or asynchronous. Excessive synchronous > IO for a process can result in noticeable stalls during direct reclaim. > Excessive IO from page reclaim may indicate that the system is seriously > under provisioned for the amount of dirty pages that exist. > > Signed-off-by: Mel Gorman Acked-by: Larry Woodman -- 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/