1307-1310

Previous Table of Contents Next

Page 1307

Routine Parallel Platform Server Maintenance

Database errors are logged throughout the Oracle system by a configurable parameter in the initSID.ora file located in the $oracle_home/dbs directory.

The default path for the Oracle system errors that the user may have seen before contacting you for advice is in $oracle_home/rdbms/log. This path may be altered by including usr dump destination in your initSID.ora file.

The tkprof tool can be used to analyze these errors if they do not seem obvious to you, or they can be faxed to Oracle for their assistance and interpretation by calling (415) 506-1500 first and speaking to an analyst who will assist you in analyses and logging a TAR with the identification by you of your temporary order number or permanent Customer Service Information (CSI) number.

Parallel Processing Database and Tool Upgrades

When you are upgrading your file server Operating System, a new version of Oracle will most likely have to be installed to support this upgrade after the new OS is installed. Prior to this, always ensure that full database exports and backups are available, and that redundant copies of the new media are available if possible.

When upgrading the Oracle source code, be sure to select "Database upgrade" from the menu and not the "Install New Database" from the orainst menu. If you do select "Install New Database" by mistake and then you enter your existing Oracle SID name , your old instance and database will be initialized or purged of all data, user IDs, and objects and will therefore be useless except as a fresh database.

If you do want to create a user test-bed or staging area, you can use the orainst installer utility for new database SID creation from your existing source code and executables.

NOTE
Before any such maintenance or installation proceeds, be sure to have full database exports and verified backups available to you, and absolutely do not use an existing Oracle SID or any current database files from your file server. Select * from SYS.DBA_DATA_FILES will echo the current status of data files, for that database only.

SQL*Net versions installed on the server must match the client versions for connection between the client and the server, when using SQL*Net.

  • SQL*Net 2.2 with the Multiple Protocol Interchange for Legacy Platforms: Allows the operation of several protocols on the network without collision across the network, or relative to the oracle SQL*Net process. Applications include the interoperability of TCP/IP, SPX/IPX, AppleTalk, and other protocols, simultaneously from disparate operating systems and to the same Oracle file server.

Page 1308

  • SQL*Net 2.2: Features dead-user detection, for the automated logoff of inactive users who have been idle for a predetermined time period. Also allows you to utilize the networking Multiple Protocol Interchange (MPI), enabling TCP/IP and SPX to run simultaneously. This SQL*Net version enables multi-threaded server connections, via a single Client/Server process (without the additional overhead of a shadow process) as well.

You must also keep or install the other SQL*Net versions that your clients may use, such as version 1.1 for Apple Macs.

Parallel Processing Platform Free Space Calculations

The current Oracle Administration guide contains the sizing calculations for both free tablespace (select * from SYS.DBA_FREE_SPACE) and table size estimates. These include the reasons why not to use percent increase other than zero in your Data Definition Language, except in high-availability systems where you may not have the option of adding a data file in an emergency. You should frequently monitor available disk space, data file free space, chained rows, and the number of extents.

To calculate Oracle block space used by an Oracle table or index, execute this query:

 Select count(distinct(substr(rowid, 1, 8)substr (rowid, 15, 4))) from tablename; 

Multiply this total by your Oracle block size (usually 2048-8192 or 32KB), giving bytes of data and deducting the Pctfree value, if any.

As with Oracle version upgrades in the future, you may want to contact Oracle at (415) 506-1500 to verify that the printed material you are using in your manual is the best and most up-to-date resource for these calculations. As the architecture shifts, these manuals become outdated and are supplemented by definitive white papers on various subjects.

For more information regarding Parallel Platform Optimization, refer to the following sources:

  • ORACLE RDBMS Performance Tuning Guide
  • Oracle Physical Database Design Guide
  • Oracle Performance Tuning and Optimization Guide

Summary

Traditionally, two distinct approaches ”shared nothing and shared disk ”have been used in the implementation of database systems on parallel hardware. Each approach in its pure form offers certain unique benefits and trade-offs. This chapter illustrated a conceptual foundation for its central argument: a hybrid Oracle architecture that combines the strengths of each approach is the most pragmatic real-world solution.

Page 1309

The TPC benchmarks are an invaluable resource for the independent verification of realistic performance gains. Conversions include fault tolerant SMP or MPP configuration, in conjunction with application migration, reengineering, and new development.

Oracle's scalable parallel architecture combines the best elements of pure shared-disk and shared-nothing approaches to provide a proven real-world architecture that enables customers to realize the true potential of parallel processing. Oracle's unique approach optimally exploits the distinct characteristics of all parallel hardware architectures ”SMP, clusters, and MPP systems ”to deliver scalable performance with superior manageability and unmatched levels of availability. As President Clinton said once, "There is no mainframe explanation for the PC [Client/Server and World Wide Web] world in which we are now living."

Page 1310

Previous Table of Contents Next


Oracle Unleashed
Oracle Development Unleashed (3rd Edition)
ISBN: 0672315750
EAN: 2147483647
Year: 1997
Pages: 391

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net