java.lang.OutOfMemoryError: GC overhead limit exceeded” exception with Sun JDK 1.6

<Error> <Kernel> <BEA-000802> <ExecuteRequest failed 
java.lang.OutOfMemoryError: GC overhead limit exceeded. 
java.lang.OutOfMemoryError: GC overhead limit exceeded 
at java.util.Arrays.copyOfRange(Arrays.java:3209) 
at java.lang.String.<init>(String.java:216) 
at java.lang.StringBuilder.toString(StringBuilder.java:430) 
at weblogic.servlet.internal.ServletRequestImpl.toString(ServletRequestImpl.java:243) 
at java.lang.String.valueOf(String.java:2827) 
Truncated. see log file for complete stacktrace

Cause

The “java.lang.OutOfMemoryError: GC overhead limit exceeded” message means that for some reason the garbage collector is taking an excessive amount of time. 

The parallel collector will throw an OutOfMemoryError if too much time is being spent in garbage collection: if more than 98% of the total time is spent in garbage collection or less than 2% of the heap is recovered by garbage collection, an OutOfMemoryError will be thrown.

This feature of throwing  ”GC overhead limit exceeded” message is designed to prevent applications from running for an extended period of time while making little or no progress because the heap is too small.

Solution

We can avoid the above “java.lang.OutOfMemoryError: GC overhead limit exceeded” exception by disabling the GC overhead limit feature in Sun JDK 1.6 by adding the following argument to the start script of JVM:

-XX:-UseGCOverheadLimit


However, please note that disabling the overhead limit only avoids getting the OutOfMemoryError at an early stage. The OutOfMemoryError is very likely to be thrown at a later stage, because it does not remove the underlying problem. You should still look into your application and JVM settings to find the cause of GC taking an excessively long time.