Enabling PMI data collection

When PMI service is enabled, the monitoring of individual components can be enabled or disabled dynamically. PMI provides four predefined statistic sets that can be used to enable a set of statistics. The following table provides details about the statistic sets. If the predefined statistic sets does not meet your monitoring requirement, the Custom option can be used to selectively enable or disable individual statistics.

Table 1. Statistic set . Enable PMI using the administrative console, wsadmin tool, or Java Virtual Machine Tool Interface (JVMTI).

Statistic set	Description
None	All statistics are disabled.
Basic	Statistics specified in J2EE 1.4, as well as popular statistics like CPU usage and live HTTP sessions are enabled. This set is enabled out-of-the-box and provides basic performance data about runtime and application components.
Extended	Basic set plus key statistics from various WebSphere® Application Server components like WLM, and dynamic caching are enabled. This set provides detailed performance data about various runtime and application components.
All	All statistics are enabled.
Custom	Enable or disable statistics selectively.

Custom setting

WebSphere Application Server Version 6.0 introduces fine-grained control to enable/disable statistics individually. The fine-grained control is available under the custom statistic set.

Sequential Update

In order to minimize the monitoring overhead, the updates to CountStatistic, AverageStatistic, and TimeStatistic are not synchronized. Since these statistic types track total and average, the extra accuracy is generally not worth the performance cost. The RangeStatistic and BoundedRangeStatistic are very sensitive; therefore, they are always are synchronized. If needed, updates to all the statistic types can be synchronized by checking the Use sequential update check box.

Intelligent Management depends on some Performance Monitoring Infrastructure (PMI) metrics. When Intelligent Management is enabled, the application server does not let you disable PMI metrics that Intelligent Management requires. However, you can add additional counters beyond the Intelligent Management PMI defaults.

Table 2. Locked PMI metrics . You cannot disable PMI metrics that Intelligent Management uses without first disabling Intelligent Management.

Locking locations	Module	Module counters locked
Nodeagent, server or on-demand router	xdProcessModule	All
Nodeagent, server or on-demand router	jvmRuntimeModule	All
Nodeagent, server or on-demand router	systemModule	All
Nodeagent, server or on-demand router	threadPoolModule	6, 7, 8
Nodeagent, server or on-demand router	xdHeapModule	All
Nodeagent, server or on-demand router	odrStatModule	All
Nodeagent	xdSystemModule	All
Server or on-demand router	DeploymentTargets	All
Server or on-demand router	xdOdrSessionModule	All
Server or on-demand router	servletSessionsModule	6, 7
Server or on-demand router	beanModule	11, 12
Server or on-demand router	webAppModule	11, 13