From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753853Ab2B0QOZ (ORCPT ); Mon, 27 Feb 2012 11:14:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43291 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752488Ab2B0QOY (ORCPT ); Mon, 27 Feb 2012 11:14:24 -0500 Message-ID: <4F4BABBA.9050207@redhat.com> Date: Mon, 27 Feb 2012 11:13:46 -0500 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120209 Thunderbird/10.0.1 MIME-Version: 1.0 To: Andi Kleen CC: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Mel Gorman , Johannes Weiner , KOSAKI Motohiro , Andrea Arcangeli , hughd@google.com Subject: Re: [PATCH -mm 2/2] mm: do not reset mm->free_area_cache on every single munmap References: <20120223145417.261225fd@cuia.bos.redhat.com> <20120223150034.2c757b3a@cuia.bos.redhat.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/23/2012 04:57 PM, Andi Kleen wrote: > Rik van Riel writes: > >> Some programs have a large number of VMAs, and make frequent calls >> to mmap and munmap. Having munmap constantly cause the search >> pointer for get_unmapped_area to get reset can cause a significant >> slowdown for such programs. > > This would be a much nicer patch if you split it into one that merges > all the copy'n'paste code and another one that actually implements > the new algorithm. The copy'n'pasted functions are not quite the same, though. All the ones that could be unified already have been, leaving a few functions with actual differences around. -- All rights reversed