Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754824AbZGJM2V (ORCPT ); Fri, 10 Jul 2009 08:28:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750918AbZGJM2L (ORCPT ); Fri, 10 Jul 2009 08:28:11 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:38034 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750809AbZGJM2K (ORCPT ); Fri, 10 Jul 2009 08:28:10 -0400 Date: Fri, 10 Jul 2009 01:42:32 +0200 From: Pavel Machek To: Marco Stornelli Cc: tim.bird@am.sony.com, jamie@shareable.org, Linux Embedded , Linux Kernel , Linux FS Devel , Daniel Walker Subject: Re: [PATCH 00/14] Pramfs: Persistent and protected ram filesystem Message-ID: <20090709234232.GB1817@ucw.cz> References: <4a4254e2.09c5660a.109d.46f8@mx.google.com> <4A425907.2060105@gmail.com> <4A42649D.6080509@gmail.com> <20090624175943.GB6618@elf.ucw.cz> <2ea1731b0906242330t5f379322sdff9880788e9b181@mail.gmail.com> <20090628085932.GA20169@elf.ucw.cz> <4A47A94E.4020808@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A47A94E.4020808@gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3190 Lines: 62 On Sun 2009-06-28 19:33:02, Marco Stornelli wrote: > Pavel Machek wrote: > >>>>> Ah now the write protection is a "needed feature", in your previous > >>>>> comment you talked about why not use ext2/3....... > >>>>> > >>>>> Marco > >>>>> > >>>> Just for your information I tried the same test with pc in a virtual machine with 32MB of RAM: > >>>> > >>>> Version 1.03e ------Sequential Output------ --Sequential Input- --Random- > >>>> -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- > >>>> Machine Size:chnk K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP > >>>> hostname 15M:1k 14156 99 128779 100 92240 100 11669 100 166242 99 80058 82 > >>>> ------Sequential Create------ --------Random Create-------- > >>>> -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- > >>>> files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP > >>>> 4 2842 99 133506 104 45088 101 2787 99 79581 101 58212 102 > >>>> > >>>> These data are the proof of the importance of the environment, workload and so on when we talk > >>>> about benchmark. Your consideration are really superficial. > >>> Unfortunately, your numbers are meaningless. > >> I don't think so. > >> > >>> (PCs should have cca 3GB/sec RAM transfer rates; and you demosstrated > >>> cca 166MB/sec read rate; disk is 80MB/sec, so that's too slow. If you > >>> want to prove your filesystem the filesystem is reasonably fast, > >>> compare it with ext2 on ramdisk.) > >>> > >> This is the point. I don't want compare it with ext2 from performance > >> point of view. This comparison makes no sense for me. I've done this > >> test to prove that if you change environment you can change in a > >> purposeful way the results. > > > > Yes, IOW you demonstrated that the numbers are machine-dependend and > > really meaningless. > > > > ext2 comparison would tell you how much pramfs sucks (or not). > > Here the test with ext2 (same environment): > > Version 1.03e ------Sequential Output------ --Sequential Input- --Random- > -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- > Machine Size:chnk K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP > hostname 15M:1k 10262 83 40847 82 38574 82 9866 92 62252 98 25204 81 > ------Sequential Create------ --------Random Create-------- > -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete-- > files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP > 1 19859 98 44804 61 68830 100 13566 99 157129 100 30431 98 > Ok, so pramfs is significantly faster than ext2. Interesting, and good for pramfs. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/