Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758563Ab1D2C6n (ORCPT ); Thu, 28 Apr 2011 22:58:43 -0400 Received: from mga02.intel.com ([134.134.136.20]:25568 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758397Ab1D2C6m (ORCPT ); Thu, 28 Apr 2011 22:58:42 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.64,284,1301900400"; d="scan'208";a="739999644" Date: Fri, 29 Apr 2011 10:58:38 +0800 From: Wu Fengguang To: Andrew Morton Cc: Minchan Kim , Dave Young , linux-mm , Linux Kernel Mailing List , Mel Gorman , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Christoph Lameter , Dave Chinner , David Rientjes Subject: Re: [RFC][PATCH] mm: cut down __GFP_NORETRY page allocation failures Message-ID: <20110429025838.GA13150@localhost> References: <20110426062535.GB19717@localhost> <20110426063421.GC19717@localhost> <20110426092029.GA27053@localhost> <20110426124743.e58d9746.akpm@linux-foundation.org> <20110428133644.GA12400@localhost> <20110429022824.GA8061@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110429022824.GA8061@localhost> 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: 1815 Lines: 64 Andrew, I tested the more realistic 100 dd case. The results are - nr_alloc_fail: 892 => 146 - reclaim delay: 4ms => 68ms Thanks, Fengguang --- base kernel, 100 dd ------------------- start time: 3 total time: 52 nr_alloc_fail 892 allocstall 131341 2nd run (no reboot): start time: 3 total time: 53 nr_alloc_fail 1555 allocstall 265718 CPU count real total virtual total delay total 962 3125524848 3113269116 37972729582 IO count delay total delay average 3 25204838 8ms SWAP count delay total delay average 0 0 0ms RECLAIM count delay total delay average 1032 5130797747 4ms (IPIs accumulated in two runs) CAL: 34898 35428 35182 35553 35320 35291 35298 35102 Function call interrupts 10ms limit, 100 dd ------------------ start time: 2 total time: 50 nr_alloc_fail 146 allocstall 10598 CPU count real total virtual total delay total 1038 3349490800 3331087137 40156395960 IO count delay total delay average 0 0 0ms SWAP count delay total delay average 0 0 0ms RECLAIM count delay total delay average 84 5795410854 68ms dd: read=0, write=0, cancelled_write=0 Thanks, Fengguang -- 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/