From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marco Stornelli Subject: Re: [PATCH 00/14] Pramfs: Persistent and protected ram filesystem Date: Sun, 28 Jun 2009 19:33:02 +0200 Message-ID: <4A47A94E.4020808@gmail.com> 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> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=qF5XVnWRBZEqzfFinCbtyyfoS//RkBbYwP+GjcQvgRs=; b=W/3cDR+HoT3JW9dSixdXRjp4gweFKSs7D/WuV8WzyoTieCjD20RuS/8iM6nv/UHeGo z7Wo8IafgDAGEDQaDVy+lPACEc7SySCfm5T8SXGtxizYARzzGTrpzDWmeOMKwZKFHmYB qM0nAEk65flbhEJmtoY1cb0Jcl3lDxo450ceM= In-Reply-To: <20090628085932.GA20169@elf.ucw.cz> Sender: linux-embedded-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Pavel Machek Cc: tim.bird@am.sony.com, jamie@shareable.org, Linux Embedded , Linux Kernel , Linux FS Devel , Daniel Walker 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). > Pavel 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 Marco