From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755100Ab2BWV5m (ORCPT ); Thu, 23 Feb 2012 16:57:42 -0500 Received: from mga01.intel.com ([192.55.52.88]:21623 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753191Ab2BWV5l (ORCPT ); Thu, 23 Feb 2012 16:57:41 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="120687770" From: Andi Kleen To: Rik van Riel 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> Date: Thu, 23 Feb 2012 13:57:42 -0800 In-Reply-To: <20120223150034.2c757b3a@cuia.bos.redhat.com> (Rik van Riel's message of "Thu, 23 Feb 2012 15:00:34 -0500") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. -Andi -- ak@linux.intel.com -- Speaking for myself only