From oracle-l-bounce@freelists.org Wed Mar 30 10:27:59 2005 Return-Path: Received: from air891.startdedicated.com (root@localhost) by orafaq.com (8.12.10/8.12.10) with ESMTP id j2UGRxJS013065 for ; Wed, 30 Mar 2005 10:27:59 -0600 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air891.startdedicated.com (8.12.10/8.12.10) with ESMTP id j2UGRxem013061 for ; Wed, 30 Mar 2005 10:27:59 -0600 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 80E918A43E; Wed, 30 Mar 2005 10:26:03 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 17401-09; Wed, 30 Mar 2005 10:26:03 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 06A0889EC4; Wed, 30 Mar 2005 10:26:02 -0500 (EST) From: "Mark W. Farnham" To: Subject: RE: sar has the correct information or the vmstat? (student projects versus "official" software) Date: Wed, 30 Mar 2005 10:18:01 -0500 Message-ID: MIME-Version: 1.0 Content-type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit In-Reply-To: <20050329232023.58611.qmail@web86908.mail.ukl.yahoo.com> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 X-archive-position: 17838 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: mwf@rsiz.com Precedence: normal Reply-To: mwf@rsiz.com X-list: oracle-l X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net X-Spam-Checker-Version: SpamAssassin 2.60 (1.212-2003-09-23-exp) on air891.startdedicated.com X-Spam-Status: No, hits=0.2 required=5.0 tests=AWL autolearn=ham version=2.60 X-Spam-Level: Connor raises an interesting question: Does the original source of software being a student project correlate with superiority or inferiority of a tool as compared to software sourced "officially?" This is a question of fact likely to go unanswered in a rigorous sense. Likely if the domain of competition is all student projects, then "official" will win, but I suspect student projects that survived into common use have the edge over all "official" software. MS-DOS, for example, was "official" software, while the Dartmouth Time Sharing System was largely a student project. A tiny number of people ever hacked DTSS. As to sar and vmstat, I've gotten varied results over the years as to which more accurately portrayed various values on which releases of which operating systems. Unless you have an independent physical measure of an operational componment that both vmstat and sar measure or way to establish a known load and have both sar and vmstat report, you can't tell for sure. Even then some of the measurements will get "Hiesenberged." Finally, at the bottom line there is the frequency of flushing of kmem structures or their analog, so you just really can't get around the problems of time slice aggregations and averaging for some of the metrics being tracked by both these tools. Usually you can find release notes or bug reports for a specific combination if one or the other is far enough off to be unreliable on a specific combination of hardware and operating system. In lieu of such notes, if you can reduce the problem to a particular system and release you can probably run a few load tests to decide whether one or the other is better in your situation. Good luck! mwf -----Original Message----- From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org]On Behalf Of Connor McDonald Sent: Tuesday, March 29, 2005 6:20 PM To: oracle-l@freelists.org Subject: Re: sar has the correct information or the vmstat? I remember at a Sun presentation once the presenter remarked that "vmstat was the official tool and 'sar' started life as a student project and should be treated as such". I dunno if thats truth or fiction. Cheers Connor -- http://www.freelists.org/webpage/oracle-l