From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lucas Meneghel Rodrigues Subject: Re: [KVM-AUTOTEST PATCH 1/2] Add KSM test Date: Tue, 29 Sep 2009 12:50:54 -0300 Message-ID: <1254239454.8179.11.camel@localhost.localdomain> References: <44701752.775351253870568755.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: dlaor@redhat.com, kvm@vger.kernel.org, autotest@test.kernel.org, Lukas Doktor To: Jiri Zupka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:63037 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752837AbZI2Puy (ORCPT ); Tue, 29 Sep 2009 11:50:54 -0400 In-Reply-To: <44701752.775351253870568755.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Fri, 2009-09-25 at 05:22 -0400, Jiri Zupka wrote: > ----- "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. First of all, sorry, I am doing the best I can to review carefully all the patch queue, and as KSM is a more involved feature that I am not very familiar with, I need a bit more time to review it! > 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. About code compiling under windows, I guess making a native windows c or c++ program is an option, I generally agree with your reasoning, this case seems to be better covered with a c program. Will get into it in more detail ASAP... > 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 > -- > 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