Garbage Collections - Selected Allocation Failure workspace

This workspace provides detailed information about the garbage-collection cycles that occurred in response to a specific heap-allocation failure that occurred within the Java™ virtual machine (JVM).

This workspace displays data provided by the Garbage Collection Cycle attributes.

Note to Solaris and HP-UX users: Allocation-failure information is not recorded on these platforms. Consequently, this workspace is always empty.

The predefined workspace contains the following items:

  • GC Elapsed Times bar chart, which breaks down the mark, sweep, and compact times (in milliseconds) for each garbage-collection cycle that occurred for the selected allocation failure
  • Heap Usage bar chart, which displays the JVM heap usage (kilobytes in use, freed, and free at start of garbage collection) for each garbage-collection cycle
  • Garbage Collections - Selected Allocation Failure report, which displays information about a single garbage-collection cycle that the JVM hosting the application server performed. For example, this report displays the free heap space both before and after garbage collection, the heap space freed, and the number of objects moved during garbage collection. For TEMA running on z/OS, region ID can be found in the ASID column.

Accessing the Garbage Collections - Selected Allocation Failure workspace

To access this workspace from the Allocation Failures workspace, use one of the following procedures:

  • From the Allocation Failures report, click the link icon to the left of any row; then, from the menu, click Garbage Collections - Selected Allocation Failure.
  • From the Allocation Failure Elapsed Times bar chart or the Heap Usage - History bar chart, right-click any bar; then, from the menu, click Link To > Garbage Collections - Selected Allocation Failure.