Heap Dump

A heap dump is a snapshot of the memory of a Java process at a certain point of time. There are different formats for persisting this data, and depending on the format it may contain different pieces of information, but in general the snapshot contains information about the java objects and classes in the heap at the moment the snapshot was triggered. Usually a full GC is triggered before the heap dump is written so it contains information about the remaining objects.

The Memory Analyzer is able to work with HPROF binary heap dumps, IBM system dumps (after preprocessing them), and IBM portable heap dumps (PHD) from a variety of platforms.

Typical information which can be found in heap dumps (once more - depending on the heap dump type) is:

A heap dump does not contain allocation information so it cannot resolve questions like who had created the objects and where they have been created.