--- old/src/share/vm/gc/parallel/psParallelCompact.cpp	2015-05-20 11:02:00.291259539 +0200
+++ new/src/share/vm/gc/parallel/psParallelCompact.cpp	2015-05-20 11:02:00.123253863 +0200
@@ -2029,7 +2029,6 @@
     // Set the number of GC threads to be used in this collection
     gc_task_manager()->set_active_gang();
     gc_task_manager()->task_idle_workers();
-    heap->set_par_threads(gc_task_manager()->active_workers());
 
     TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
     GCTraceTime t1(GCCauseString("Full GC", gc_cause), PrintGC, !PrintGCDetails, NULL, _gc_tracer.gc_id());