--- old/src/share/vm/runtime/thread.cpp	2020-01-27 23:21:02.000000000 -0800
+++ new/src/share/vm/runtime/thread.cpp	2020-01-27 23:21:02.000000000 -0800
@@ -3677,6 +3677,11 @@
   StatSampler::engage();
   if (CheckJNICalls)                  JniPeriodicChecker::engage();
 
+  if (AsyncGCLogging && Arguments::gc_log_filename() != NULL) {
+    PeriodicTask* task = new GCLogFlusher(GCLogFlushInterval, static_cast<gcLogFileStream* >(gclog_or_tty));
+    task->enroll();
+  }
+
   BiasedLocking::init();
 
 #if INCLUDE_RTM_OPT