From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754902Ab3AaAFt (ORCPT ); Wed, 30 Jan 2013 19:05:49 -0500 Received: from mail-pa0-f46.google.com ([209.85.220.46]:63682 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753229Ab3AaAFr (ORCPT ); Wed, 30 Jan 2013 19:05:47 -0500 Message-ID: <1359590736.1557.0.camel@kernel> Subject: Re: [PATCH 0/11] ksm: NUMA trees and page migration From: Ric Mason To: Andrea Arcangeli Cc: Izik Eidus , Andrew Morton , Hugh Dickins , Petr Holasek , Rik van Riel , David Rientjes , Anton Arapov , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org Date: Wed, 30 Jan 2013 18:05:36 -0600 In-Reply-To: <20130129165125.GA17671@redhat.com> References: <20130128155452.16882a6e.akpm@linux-foundation.org> <51071CA0.801@ravellosystems.com> <51073345.4070605@ravellosystems.com> <20130129165125.GA17671@redhat.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4 (3.4.4-2.fc17) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2013-01-29 at 17:51 +0100, Andrea Arcangeli wrote: > Hi everyone, > > On Tue, Jan 29, 2013 at 04:26:13AM +0200, Izik Eidus wrote: > > On 01/29/2013 02:49 AM, Izik Eidus wrote: > > > On 01/29/2013 01:54 AM, Andrew Morton wrote: > > >> On Fri, 25 Jan 2013 17:53:10 -0800 (PST) > > >> Hugh Dickins wrote: > > >> > > >>> Here's a KSM series > > >> Sanity check: do you have a feeling for how useful KSM is? > > >> Performance/space improvements for typical (or atypical) workloads? > > >> Are people using it? Successfully? > > > > > > BTW, After thinking a bit about the word people, I wanted to see if > > normal users of linux > > that just download and install Linux (without using special > > virtualization product) are able to use it. > > So I google little bit for it, and found some nice results from users: > > http://serverascode.com/2012/11/11/ksm-kvm.html > > > > But I do agree that it provide justifying value only for virtualization > > users... > > Mostly for virtualization users indeed, but I'm aware of a few non > virtualization users too: > > 1) CERN has been one of the early adopters of KSM and initially they > were using KSM standalone (probably because not all hypervisors they > had to deal with were KVM/linux based, while all guests were linux and > in turn KSM capable). More info in the KSM paper page 2: > > http://www.kernel.org/doc/ols/2009/ols2009-pages-19-28.pdf > > However lately they're running KSM in combination with KVM too, and I'm > not sure if they're still using it standalone. See the "KSM shared" > blue area in slide 12 and the comparison with KSM on and off in slide > 14. > > https://indico.fnal.gov/getFile.py/access?contribId=18&sessionId=4&resId=0&materialId=slides&confId=4986 > > 2) all recent cyanogenmod in the performance menu in settings supports > KSM out of the box. You can run it for a while and then shut it > off. > > Not sure how good idea it is to leave it always on, but the only > efficient cellphone/tablet powersaving design (i.e. the wakelocks + > suspend to ram) still won't waste energy while the screen is off and > the phone has suspended to ram, regardless of KSM on or off. > > KSM NUMA awareness however is not needed on the cellphone :). Thanks for your sharing. Is there ksm benchmark? How to get it? > > -- > 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