From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Zupka Subject: Re: [KVM-AUTOTEST PATCH 1/2] Add KSM test Date: Fri, 25 Sep 2009 05:22:48 -0400 (EDT) Message-ID: <44701752.775351253870568755.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> References: <830286859.775301253870289468.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, autotest@test.kernel.org, Lukas Doktor To: dlaor@redhat.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50512 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751397AbZIYJWq (ORCPT ); Fri, 25 Sep 2009 05:22:46 -0400 In-Reply-To: <830286859.775301253870289468.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: ----- "Dor Laor" wrote: > On 09/16/2009 04:09 PM, Jiri Zupka wrote: > > > > ----- "Dor Laor" wrote: > > > >> On 09/15/2009 09:58 PM, Jiri Zupka wrote: > >>>> After a quick review I have the following questions: > >>>> 1. Why did you implement the guest tool in 'c' and not in > python? > >>>> Python is much simpler and you can share some code with the > >> server. > >>>> This 'test protocol' would also be easier to understand this > >> way. > >>> > >>> We need speed and the precise control of allocate memory in > pages. > >>> > >>>> 2. IMHO there is no need to use select, you can do blocking > read. > >>> > >>> We replace socket communication by interactive program > communication > >> via ssh/telnet > >>> > >>>> 3. Also you can use plain malloc without the more complex ( a > bit) > >> mmap. > >>> > >>> We need address exactly the memory pages. We can't allow shift of > >> the data in memory. > >> > >> You can use the tmpfs+dd idea instead of the specific program as I > >> detailed before. Maybe some other binary can be used. My intention > is > >> to > >> simplify the test/environment as much as possible. > >> > > > > We need compatibility with others system, like Windows etc.. > > We want to add support for others system in next version > > KSM is a host feature and should be agnostic to the guest. > Also I don't think your code will compile on windows... Yes, I think you have true. But because we need generate special data to pages in memory. We need use script on guest side of test. Because communication over ssh is to slow to transfer lot of GB of special data to guests. We can use optimized C program which is 10x and more faster than python script on native system. Heavy load of virtual guest can make some performance problem. We can use tmpfs but with python script to generate special data. We can't use dd with random because we need test some special case. (change only last 96B of page etc.. ) What do you think about it? > > > > >> > >>> -- > >>> To unsubscribe from this list: send the line "unsubscribe kvm" in > >>> the body of a message to majordomo@vger.kernel.org > >>> More majordomo info at > http://vger.kernel.org/majordomo-info.html > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html