From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751600AbZHHFrQ (ORCPT ); Sat, 8 Aug 2009 01:47:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751211AbZHHFrP (ORCPT ); Sat, 8 Aug 2009 01:47:15 -0400 Received: from mail-yx0-f175.google.com ([209.85.210.175]:55346 "EHLO mail-yx0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbZHHFrO convert rfc822-to-8bit (ORCPT ); Sat, 8 Aug 2009 01:47:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=OoH51+W+uv32xP15glCtf1mrDNIbO9lsuiegZr9oOcxUMx6ghtFcXlOrsXGkQRde9l dqxH9wSnXCX6f0TdPIPvNQPXpxwOR5pxrH1vEn67x3EdPxHJ8fOMqmgGqy+THkychb2M LMTYujm4e61nhxoVETwFpsQjR/RBX6NWR82LE= MIME-Version: 1.0 In-Reply-To: <1249666815-28784-2-git-send-email-mel@csn.ul.ie> References: <1249666815-28784-1-git-send-email-mel@csn.ul.ie> <1249666815-28784-2-git-send-email-mel@csn.ul.ie> Date: Sat, 8 Aug 2009 14:47:13 +0900 X-Google-Sender-Auth: d62748086717695a Message-ID: <2f11576a0908072247y3d17c977i31ea3bca82058083@mail.gmail.com> Subject: Re: [PATCH 1/6] tracing, page-allocator: Add trace events for page allocation and page freeing From: KOSAKI Motohiro To: Mel Gorman Cc: Larry Woodman , Ingo Molnar , Andrew Morton , riel@redhat.com, Peter Zijlstra , LKML , linux-mm@kvack.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2009/8/8 Mel Gorman : > This patch adds trace events for the allocation and freeing of pages, > including the freeing of pagevecs.  Using the events, it will be known what > struct page and pfns are being allocated and freed and what the call site > was in many cases. > > The page alloc tracepoints be used as an indicator as to whether the workload > was heavily dependant on the page allocator or not. You can make a guess based > on vmstat but you can't get a per-process breakdown. Depending on the call > path, the call_site for page allocation may be __get_free_pages() instead > of a useful callsite. Instead of passing down a return address similar to > slab debugging, the user should enable the stacktrace and seg-addr options > to get a proper stack trace. > > The pagevec free tracepoint has a different usecase. It can be used to get > a idea of how many pages are being dumped off the LRU and whether it is > kswapd doing the work or a process doing direct reclaim. > > Signed-off-by: Mel Gorman > Acked-by: Rik van Riel Looks good to me. Reviewed-by: KOSAKI Motohiro