From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrea Arcangeli Subject: Re: [patch 5/9] Convert anon_vma lock to rw_sem and refcount Date: Wed, 2 Apr 2008 19:50:58 +0200 Message-ID: <20080402175058.GR19189@duo.random> References: <20080401205531.986291575@sgi.com> <20080401205636.777127252@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20080401205636.777127252@sgi.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net To: Christoph Lameter Cc: steiner@sgi.com, Peter Zijlstra , linux-mm@kvack.org, Kanoj Sarcar , Roland Dreier , Steve Wise , linux-kernel@vger.kernel.org, Avi Kivity , kvm-devel@lists.sourceforge.net, daniel.blueman@quadrics.com, Robin Holt , general@lists.openfabrics.org, Hugh Dickins List-Id: linux-mm.kvack.org On Tue, Apr 01, 2008 at 01:55:36PM -0700, Christoph Lameter wrote: > This results in f.e. the Aim9 brk performance test to got down by 10-15%. I guess it's more likely because of overscheduling for small crtitical sections, did you counted the total number of context switches? I guess there will be a lot more with your patch applied. That regression is a showstopper and it is the reason why I've suggested before to add a CONFIG_XPMEM or CONFIG_MMU_NOTIFIER_SLEEP config option to make the VM locks sleep capable only when XPMEM=y (PREEMPT_RT will enable it too). Thanks for doing the benchmark work! ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace