From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f43.google.com (mail-pb0-f43.google.com [209.85.160.43]) by kanga.kvack.org (Postfix) with ESMTP id BBEFD6B0037 for ; Mon, 3 Feb 2014 03:24:33 -0500 (EST) Received: by mail-pb0-f43.google.com with SMTP id md12so6781001pbc.2 for ; Mon, 03 Feb 2014 00:24:33 -0800 (PST) Received: from e23smtp05.au.ibm.com (e23smtp05.au.ibm.com. [202.81.31.147]) by mx.google.com with ESMTPS id r7si19642095pbk.117.2014.02.03.00.24.31 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Mon, 03 Feb 2014 00:24:32 -0800 (PST) Received: from /spool/local by e23smtp05.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 3 Feb 2014 18:24:27 +1000 Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [9.190.234.120]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id BB2F03578052 for ; Mon, 3 Feb 2014 19:24:21 +1100 (EST) Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s138546o60162170 for ; Mon, 3 Feb 2014 19:05:04 +1100 Received: from d23av04.au.ibm.com (localhost [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s138OL4J008571 for ; Mon, 3 Feb 2014 19:24:21 +1100 Message-ID: <52EF53B5.6050203@linux.vnet.ibm.com> Date: Mon, 03 Feb 2014 14:00:45 +0530 From: Raghavendra K T MIME-Version: 1.0 Subject: Re: [RFC PATCH V5] mm readahead: Fix readahead fail for no local memory and limit readahead pages References: <1390388025-1418-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> In-Reply-To: <1390388025-1418-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Raghavendra K T , Fengguang Wu , David Cohen , Al Viro , Damien Ramonda , Jan Kara , Linus , linux-mm@kvack.org, linux-kernel@vger.kernel.org On 01/22/2014 04:23 PM, Raghavendra K T wrote: > max_sane_readahead returns zero on the cpu having no local memory > node. Fix that by returning a sanitized number of pages viz., > minimum of (requested pages, 4k) > > Result: > fadvise experiment with FADV_WILLNEED on a x240 machine with 1GB testfile > 32GB* 4G RAM numa machine ( 12 iterations) yielded > > Kernel Avg Stddev > base 7.2963 1.10 % > patched 7.2972 1.18 % > > Reviewed-by: Jan Kara > Signed-off-by: Raghavendra K T > --- Could you please let me know what do you feel about the patch ? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org