WebLogic Garbage Collection

Garbage Collection in WebLogic Server AdministrationWebLogic Force Garbage Collection(GC)

What is Garbage Collection(GC)??

·         Objects of interest

·         Principal notions

·         Classic examples with assumptions and properties

Introduction:

·         Identifying garbage and deallocating the memory it occupies is called Garbage Collection(GC)

·         We can try to handle the GC to object allocation and deallocation ourselves.

·         GC is concerned with the automatic reclamation of dynamically allocated memory after its last used by a program.

Dynamically Memory Allocation:

·         Also: heap-allocated memory

·         Allocation: malloc,new,…..

Before first usage

·         Deallocation: free,delete,dispose,……

After last usage

·         Needed for

    C++,Java: objects

    SML: datatypes,procedures

    Anything that outlives procedure call

Getting it Wrong

·         Forget to free (memory leak)

Program eventually runs out of memory

Long running programs: OSs, Servers,….

·         Free to early (dangling pointer)

Lucky: illegal access detected by OS

Horror: memory reused, in simultaneous use

·         Programs can behave arbitrarily

·         Crashes might happen much later

GC is help full in case you are seeing your JVM heap usage is very high constantly.

   Login to WebLogic Admin Console

 Goto àEnvironment à Servers à(select your server)

Goto à Monitoring àPerformance

Click Garbage Collect