diff -r 2c3cc4b01880 -r c16ac7a2eba4 src/hotspot/share/jfr/periodic/jfrPeriodic.cpp
--- a/src/hotspot/share/jfr/periodic/jfrPeriodic.cpp	Wed Oct 30 16:14:56 2019 +0100
+++ b/src/hotspot/share/jfr/periodic/jfrPeriodic.cpp	Wed Oct 30 19:43:52 2019 +0100
@@ -44,6 +44,7 @@
 #include "jfr/periodic/jfrNetworkUtilization.hpp"
 #include "jfr/recorder/jfrRecorder.hpp"
 #include "jfr/support/jfrThreadId.hpp"
+#include "jfr/utilities/jfrThreadIterator.hpp"
 #include "jfr/utilities/jfrTime.hpp"
 #include "jfrfiles/jfrPeriodic.hpp"
 #include "logging/log.hpp"
@@ -56,7 +57,6 @@
 #include "runtime/os.hpp"
 #include "runtime/os_perf.hpp"
 #include "runtime/thread.inline.hpp"
-#include "runtime/threadSMR.hpp"
 #include "runtime/sweeper.hpp"
 #include "runtime/vmThread.hpp"
 #include "services/classLoadingService.hpp"
@@ -410,13 +410,12 @@
   GrowableArray<jlong> allocated(initial_size);
   GrowableArray<traceid> thread_ids(initial_size);
   JfrTicks time_stamp = JfrTicks::now();
-  {
-    // Collect allocation statistics while holding threads lock
-    MutexLocker ml(Threads_lock);
-    for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
-      allocated.append(jt->cooked_allocated_bytes());
-      thread_ids.append(JFR_THREAD_ID(jt));
-    }
+  JfrJavaThreadIterator iter;
+  while (iter.has_next()) {
+    JavaThread* const jt = iter.next();
+    assert(jt != NULL, "invariant");
+    allocated.append(jt->cooked_allocated_bytes());
+    thread_ids.append(JFR_THREAD_ID(jt));
   }
 
   // Write allocation statistics to buffer.