-XsamplingExpirationTime

Disables JIT sampling after a specified amount of time.

When the JIT sampling thread is disabled, no processor cycles are used by an idle OpenJ9 VM.

Use this option with care; after the sampling thread is disabled, you cannot reactivate it. However, because the profiling frequency is automatically reduced, you should not have to use this option.

Allow the sampling thread to run for long enough to identify important optimizations.

Syntax

    -XsamplingExpirationTime<time>
where <time> is specified in seconds.

Explanation

The JIT sampling thread profiles the running Java™ application to discover commonly used methods. The memory and processor usage of the sampling thread is negligible, and the frequency of profiling is automatically reduced when the OpenJ9 VM is idle, to once per second instead of once every 10ms, or once every 100 seconds if the idle state lasts more than 50 seconds.