From oracle-l-bounce@freelists.org Wed Jun 16 14:46:49 2004 Return-Path: Received: from air189.startdedicated.com (root@localhost) by orafaq.com (8.11.6/8.11.6) with ESMTP id i5GJkOE11195 for ; Wed, 16 Jun 2004 14:46:34 -0500 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air189.startdedicated.com (8.11.6/8.11.6) with ESMTP id i5GJkB611168 for ; Wed, 16 Jun 2004 14:46:21 -0500 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id CACCB72D2AC; Wed, 16 Jun 2004 14:30:08 -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 12267-77; Wed, 16 Jun 2004 14:30:08 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 192CD72C7AF; Wed, 16 Jun 2004 14:30:08 -0500 (EST) Received: with ECARTIS (v1.0.0; list oracle-l); Wed, 16 Jun 2004 14:28:46 -0500 (EST) X-Original-To: oracle-l@freelists.org Delivered-To: oracle-l@freelists.org Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 4C8DC72CF83 for ; Wed, 16 Jun 2004 14:28:45 -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 12934-32 for ; Wed, 16 Jun 2004 14:28:45 -0500 (EST) Received: from troll.tpk.net (mail.tpk.net [216.107.198.11]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id A634772CE13 for ; Wed, 16 Jun 2004 14:28:44 -0500 (EST) Received: from MWF600XL (host216-107-212-43.tpk.net [216.107.212.43]) by troll.tpk.net (Postfix) with SMTP id 18B9510238C for ; Wed, 16 Jun 2004 15:49:13 -0400 (EDT) From: "Mark W. Farnham" To: Subject: RE: db file scattered/sequential read wait Date: Wed, 16 Jun 2004 15:43:31 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.6604 (9.0.2911.0) Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 In-Reply-To: <1087410064.40d08f906c010@webmail.hosting.telus.net> X-Virus-Scanned: by amavisd-new at freelists.org X-archive-position: 2834 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: oracle-l@freelists.org X-list: oracle-l X-Virus-Scanned: by amavisd-new at freelists.org certainly correct. the query was not mine by the way, just the endpoint fixup. I gathered from the thread that the inquiry was from someone who had an individual object getting seriously pounded on. Excellent idea to keep an efficient map populated in the wee hours (aka "load valley" for global operations)! mwf -----Original Message----- From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org]On Behalf Of Wolfgang Breitling Sent: Wednesday, June 16, 2004 2:21 PM To: oracle-l@freelists.org Subject: RE: db file scattered/sequential read wait Just a word of caution. You don't want to run this query every time you want to find out the object for a db file read. That alone could bring your system to its knees, especially if you have LMTs - and if not, why not? (those who still manage Oracle 7 and lower systems are excused). I run something like that in the wee hours of the morning when there is spare capacity and load the response into a table indexed by file# and block#. This way I don't go after the catalog tables and the response is immediate. Sure, I risk missing the occasional block (hasn't happened yet) if the object went into a new extent after I ran my report. Quoting "Mark W. Farnham" : > I think you want a minus one in the second term. > > Let's see, if block_id = 1 and you read 8 blocks, then 1...9, is *not* what > you want, so yeah, (block_id+blocks-1) > would tighten up that predicate. > > mwf > -- regards Wolfgang Breitling, Oracle 7,8,8i,9i OCP DBA; Oaktable member Centrex Consulting Corporation www.centrexcc.com ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------