Improving the performance of single instance Oracle on file systems, January 2008

Introduction

HP SG SMS includes seven product bundles

, four of which provide a robust, feature-rich environment

for Oracle database installations. In combination, HP Serviceguard and Veritas Storage Foundation

provide a solid base for enterprise applications that must run with exceptional availability while

providing a foundation that is reliable, is easy-to-manage, and gets the best performance from the

hardware platform it runs on.

Traditionally, database administrators implemented databases on raw devices or raw volumes to get

the best performance from their hardware. Some loss of manageability is incurred in those

implementations, but better performance was the key factor in choosing raw devices or raw volumes

over file systems.

Oracle Disk Manager (ODM) is an API specifically tailored to Oracle Database to maximize the I/O

performance on file systems. ODM enables asynchronous I/O, making it possible to provide the

functionality of a file system-based environment without compromising the performance traditionally

associated with raw configurations.

In the SG SMS bundles for Oracle, an implementation of ODM is provided for Online JFS (also

known as the Veritas File System, or VxFS). This ODM library is a key performance acceleration

feature, supporting Online JFS and Cluster File System (CFS). It can be used for single-instance Oracle

and Oracle RAC databases (9i and later).

Purpose

This paper presents the results of tests with a single-instance Oracle database so system architects can

make informed decisions when choosing an I/O subsystem configuration. These tests show that ODM

provides real value in performance, especially where ease of manageability of a file system is

essential.

For this benchmark, we used SG SMS A.01.00 bundle T2773BA.

We focus on a single-instance Oracle database in a variety of configurations, to quantify the

performance differences on file systems and raw volumes and to determine performance gains that

can be achieved using ODM.

The following I/O subsystem configurations were tested:

• Online JFS on VxVM with ODM

• Online JFS on VxVM

• Online JFS on LVM

• Raw volumes on LVM

• Raw volumes on VxVM

Another White Paper

examines the relative performance of Oracle Real Application Clusters (RAC)

with CFS and ODM versus raw volumes using Shared Logical Volume Manager (SLVM).

Note

HP recommends that a chosen solution be tested to verify that it meets the

expected peak performance needs using the actual target application.

Doing this in an environment that is identical to the production environment

is the most effective way to estimate system behavior.

For a description of all HP SG SMS bundles, please refer to http://hp.com/go/sms.

“Performance Analysis of the HP Serviceguard Storage Management Suite for Oracle Database” at

http://h20247.www2.hp.com/enterprise/downloads/PerfAnalysis_OracleDB_HPServiceguard.pdf