Java: does GarbageCollectorMBean.getCollectionTime return pause time or something else?

Question

Oracle javadoc for GarbageCollectorMBean.getCollectionTime says: "Returns the estimated accumulated collection time in milliseconds." Is this a pause time, or is it generally the time spent on any garbage collector threads?

Answer 1

GarbageCollectorMBean.getCollectionTime () returns the cumulative wall clock time in milliseconds for a particular algorithm.

For Stop-the-World algorithms (usually for young collections) this can be interpreted as a temporary application has been suspended.

, STW, ( , ).

, GC, ( , ).