WLMTK Overview: Using HP-UX WLM Effectively With Your Most Critical Applications

The remainder of this white paper discusses the benefits of each of these toolkits and how to use them.

HP-UX WLM Oracle Database Toolkit

HP-UX WLM enables you to place Oracle instances and other applications in their own WLM

workloads. With the instances and applications separated, WLM then manages the performance of

each instance and application through prioritized SLOs. For the Oracle database administrator, this

functionality provides the ability to allocate different CPU resources to Oracle database instances by

modifying the WLM configuration.

Oracle instances and applications are separated between separate Oracle database instances—not

within a single instance. That is, all Oracle processes related to a specific database instance must be

assigned to the same workload, including Oracle server processes (“shadow” processes) that run on

behalf of users accessing the database.

To take advantage of the ability of WLM’s capabilities with respect to Oracle instances, HP provides

HP-UX Workload Manager Oracle Database Toolkit (ODBTK), which facilitates transferring metrics

from Oracle database instances into WLM. This toolkit, which is included with WLM, works with

Oracle 8.0.x, Oracle 8.1.5, Oracle 8.1.6, Oracle 8.1.7, and Oracle 9.0.1. For information on

toolkit requirements, see the HP-UX Workload Manager Toolkits User’s Guide.

What metrics are available?

The following database metrics are available:

• Time elapsed while user-defined SQL code executes (this metric provides a response-time

measurement for the database)

• Application-specific value returned by executed SQL code

• Information retrieved from Oracle V$ tables using SQL (these tables provide dynamic performance

data for Oracle instances and enable the Oracle database administrator to see current performance

information)

Why use ODBTK?

The main benefit of using Oracle database metrics with WLM is that you can use these metrics to

manage the performance of your instances. For the instances, you can specify SLOs based on the

metrics.

The following sections illustrate a few reasons for using ODBTK to manage your instances. These

sections discuss various items you would set in an SLO in a WLM configuration file. ODBTK comes

with example WLM configuration files. These files, some of which are used as a basis for the

following examples, show how you can control your Oracle instances and their resources quickly and

easily.

The following examples focus on a single instance to simplify demonstrating what WLM and ODBTK

can accomplish. Of course, WLM is most useful when multiple database instances and applications

are running on a single system.

Set response time goals

In this first example, a workload named Instance1 has an SLO with priority 1, the highest possible

priority. However, other workloads might also have priority 1 SLOs. The workload’s CPU allocation

will be in the range of 20 to 80% of the system CPU resources, assuming enough CPU resources are

available to meet this SLO and all other SLOs at priority 1. WLM adjusts the CPU allocation for the

instance’s workload within this range so that the response time for the ”Select” database operation is

less than 10 seconds.