--- a/src/hotspot/share/gc/g1/g1ParScanThreadState.cpp	Mon Oct 29 08:52:04 2018 +0100
+++ b/src/hotspot/share/gc/g1/g1ParScanThreadState.cpp	Mon Oct 29 08:55:03 2018 +0100
@@ -203,7 +203,7 @@
   if (alloc_buf->contains(obj_ptr)) {
     _g1h->_gc_tracer_stw->report_promotion_in_new_plab_event(old->klass(), word_sz * HeapWordSize, age,
                                                              dest_state.value() == InCSetState::Old,
-                                                             alloc_buf->word_sz());
+                                                             alloc_buf->word_sz() * HeapWordSize);
   } else {
     _g1h->_gc_tracer_stw->report_promotion_outside_plab_event(old->klass(), word_sz * HeapWordSize, age,
                                                               dest_state.value() == InCSetState::Old);