66 Performance Tuning for Content Manager
There are two basic types of content from the caching point of view:
Static content does not change over long periods of time. The content type
can be HTML, JSP rendering less dynamic data, GIF, and JPG.
Dynamic content includes frequently updated content (such as stock
exchange rates), as well as personalized and customized content. Although it
is changing content, it also must be stable over a long enough time for
meaningful reuse to occur. However, if some content is very frequently
accessed, such as requests for pricing information of a popular stock, then
even a short time of stability might be long enough to benefit from caching.
Java Virtual Machine Profiler Interface
The Java Virtual Machine Profiler Interface (JVMPI) enables the collection of
information, such as data about garbage collection, and the Java virtual machine
(JVM) API that runs the application server. The Tivoli Performance Viewer
leverages a JVMPI to enable more comprehensive performance analysis.
JVMPI is a two-way function call interface between the JVM API and an
in-process profiler agent. The JVM API notifies the profiler agent of various
events, such as heap allocations and thread starts. The profiler agent can activate
or deactivate specific event notifications based on the needs of the profiler.
JVMPI supports partial profiling by enabling the user to choose which types of
profiling information to collect and to select certain subsets of the time during
which the JVM API is active. JVMPI moderately increases the performance
Parameter hot list
Each WebSphere Application Server process has several parameters that
influence application performance. You can use the WebSphere Application Server
Administrative Console to configure and tune applications, Web containers, EJB
containers, application servers, and nodes in the administrative domain.
Always review the tuning parameter hot list, which is a subset of the tuning
parameter index. These parameters have an important impact on performance.
Because these parameters are application dependent, the parameter settings for
specific applications and environments can vary.
2.2.5 Routine maintenance
WebSphere Application Server collects data about runtime and applications
through the Performance Monitoring Infrastructure (PMI). Performance data can
then be monitored and analyzed with a variety of tools.