How to find a Java Memory Leak

by

I use following approach to finding memory leaks in Java. I’ve used jProfiler with great success, but I believe that any specialized tool with graphing capabilities (diffs are easier to analyze in graphical form) will work.

  1. Start the application and wait until it get to “stable” state, when all the initialization is complete and the application is idle.
  2. Run the operation suspected of producing a memory leak several times to allow any cache, DB-related initialization to take place.
  3. Run GC and take memory snapshot.
  4. Run the operation again. Depending on the complexity of operation and sizes of data that is processed operation may need to be run several to many times.
  5. Run GC and take memory snapshot.
  6. Run a diff for 2 snapshots and analyze it.

Basically analysis should start from greatest positive diff by, say, object types and find what causes those extra objects to stick in memory.

For web applications that process requests in several threads analysis gets more complicated, but nevertheless general approach still applies.

I did quite a number of projects specifically aimed at reducing memory footprint of the applications and this general approach with some application specific tweaks and trick always worked well.

More Related Contents:

  1. How can I create a memory leak in Java?
  2. How to set the maximum memory usage for JVM?
  3. General strategy to resolve Java memory leak?
  4. Circular References in Java
  5. substring method in String class causes memory leak [duplicate]
  6. How ‘random’ is allocation of memory when I say “new Integer” in Java?
  7. What is a StackOverflowError?
  8. Recommendations for a heap analysis tool for Java? [closed]
  9. What is the memory consumption of an object in Java?
  10. Virtual Memory Usage from Java under Linux, too much memory used
  11. How is the java memory pool divided?
  12. When exactly is it leak safe to use (anonymous) inner classes?
  13. Resource leak: ‘in’ is never closed
  14. Size of a byte in memory – Java
  15. How to tune Tomcat 5.5 JVM Memory settings without using the configuration program
  16. What is the default stack size, can it grow, how does it work with garbage collection?
  17. ThreadLocal & Memory Leak
  18. Relation between memory host and memory arguments xms and xmx from Java
  19. Eclipse memory settings when getting “Java Heap Space” and “Out of Memory”
  20. What is an “internal address” in Java?
  21. Java still uses system memory after deallocation of objects and garbage collection
  22. Limit jvm process memory on ubuntu
  23. Java: A two dimensional array is stored in column-major or row-major order?
  24. Arrays in Java and how they are stored in memory
  25. Memory-efficient sparse array in Java
  26. what is the use of MemoryFile in android
  27. Rounding Errors?
  28. Is the garbage collector guaranteed to run before Out of Memory Error?
  29. Steps in the memory allocation process for Java objects
  30. Do unclosed streams cause memory leaks in java?

Leave a Comment