WebSphere Application Server V7.0: Concepts ... - IBM Redbooks

synthetic transactions or to track the performance of a specific transaction. By
using test transactions, you can measure performance of the site end-to-end.
From a performance perspective, using transaction request metrics can aid in
determining if an application is meeting service level agreements (SLAs) for the
client. The metrics can be used to alert the user when an SLA target is not met.
Request metrics help administrators answer the following questions:
► What performance area should the user be focused on?
► Is there too much time being spent on any given area?
► How do I determine if response times for transactions are meeting their goals
and do not violate the SLAs
Those familiar with the Application Response Measurement (ARM) standard
know that beginning in WebSphere Application Server V5.1, the environment
was ARM 4.0 compliant. WebSphere Application Server V6 extended the
attributes measured to include Web services, JMS, and asynchronous beans.
Implementing request metrics
There are several methods for implementing request metrics. This section briefly
discusses the methods that are currently available.
Request filtering
The most common method of implementing request metrics is to use request
filtering. In this method, you use filters to limit the number of transactions that are
logged, capturing only those transactions you care to monitor. As an example,
you can use an IP address filter to monitor synthetic transactions that always
come from the same server. Some of the available filters are as follows:
► HTTP requests: Filtered by IP address, URI, or both
► Enterprise bean requests: Filtered by method name
► JMS requests: Filtered by parameters
► Web services requests: Filtered by parameters
► Source IP filters
The performance impact is less than 5% when all incoming transactions are
being instrumented. This is not a significant amount, but factor this in when
implementing the metrics. The path for implementation in the Integrated
Solutions Console is through Monitoring and Tuning → Request Metrics.
274 WebSphere Application Server V7.0: Concepts, Planning, and Design