What is CMS garbage collector tuning: -XX:ConcGCThreads?

Usage:

You can set the number of threads used for concurrent GC:

-XX:ConcGCThreads=xxx,  where xxx is desired number of threads.

Examples:

To set the number of threads for concurrent GC to 4 use:

-XX:ConcGCThreads=4

Description:

The Concurrent Mark Sweep (CMS) GC uses multiple threads for it’s regular garbage collection routine. It's designed for applications that prefer shorter garbage collection pauses, and can afford to share processor resources with the garbage collector while the application is running. We can tune CMS GC with additional options, one of them is ConcGCThreads. It sets the number of threads used for concurrent GC. Sets threads to approximately 1/4 of the number of parallel garbage collection threads. The default value depends on the number of CPUs available to the JVM.

Default Value:

Default value platform-dependent .

Errors:

None

Arguments related:

TODO link USeParNewGC, MaxHeapSize, MinHeapFreeRatio, MaxHeapFreeRatio, Xmx, Xms

Related Posts:

• Quick start on Java GC
• Garbage collection tuning
• Garbage collectors documentation
• Quick start on Java GC

NOTE:

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