What to pay attention to when analyzing Heap Dump?

When analyzing a Heap Dump in Java, it is important to pay attention to the following points:

• Memory sizes occupied by different classes — identify which objects occupy the most memory.
• Number of object instances — may indicate leaks if objects are not released.
• Retained set (retaining references tree) — understand why objects are not collected by the garbage collector.
• Objects with long lifetimes — often the roots of leaks.
• Memory distribution patterns — for example, a large number of identical strings or collections.
• Checking weak and strong references — to understand which objects are accessible for GC.

Tools commonly used for analysis include:

• VisualVM
• Eclipse MAT (Memory Analyzer Tool)
• JProfiler

Example: if a Heap Dump contains many instances of the class Session that are not released, it is necessary to check where they are created and why references to them are not removed.

Thus, Heap Dump analysis helps identify memory leaks, inefficient memory usage, and optimize application performance.