What is PS Eden space in JVM?
Eden Space: The pool from which memory is initially allocated for most objects. Survivor Space: The pool containing objects that have survived the garbage collection of the Eden space. Tenured Generation or Old Gen: The pool containing objects that have existed for some time in the survivor space.
What happens when Eden space is full?
When Eden space is filled with objects, Minor GC is performed and all the survivor objects are moved to one of the survivor spaces. Minor GC also checks the survivor objects and move them to the other survivor space. Objects that are survived after many cycles of GC, are moved to the Old generation memory space.
What is Eden space in GC?
Eden Space (heap): The pool from which memory is initially allocated for most objects. Survivor Space (heap): The pool containing objects that have survived the garbage collection of the Eden space.
Does G1GC stop the world?
G1GC (Garbage First Garbage Collector) is the low latency garbage collection algorithm included in recent versions of both OpenJDK and Oracle Java. Like other Java GC algorithms, to reclaim heap space G1GC must halt all application threads, a process referred to as stopping-the-world (STW) or pausing (a GC pause).
Why is there 2 Survivor spaces?
Survivor spaces: These two small spaces keep the surviving objects of a young generation garbage collection. Surviving objects will be copied for a (small) number of times from one survivor into the other. This allows to harvest our more dereferenced objects.
What is SurvivorRatio?
The SurvivorRatio parameter controls the size of the two survivor spaces. For example, -XX:SurvivorRatio=6 sets the ratio between each survivor space and eden to be 1:6, each survivor space will be one eighth of the young generation. The default for Solaris is 32.
What is :+ UseG1GC?
-XX:+UseG1GC – Tells the JVM to use the G1 Garbage collector. -XX:MaxGCPauseMillis=200 – Sets a target for the maximum GC pause time. This is a soft goal, and the JVM will make its best effort to achieve it.
What is XX MaxGCPauseMillis?
-XX:MaxGCPauseMillis: Sets a target for the maximum GC pause time. This is a soft goal, and the JVM will make its best effort to achieve it.
What is G1HeapRegionSize?
The G1 GC is an adaptive garbage collector with defaults that enable it to work efficiently without modification. You can adapt and tune the G1 GC to your application performance needs by entering the following options with changed settings on the JVM command line. -XX:G1HeapRegionSize=n. Sets the size of a G1 region.