--- a/src/hotspot/share/runtime/threadHeapSampler.cpp	Wed Sep 05 09:12:50 2018 -0700
+++ b/src/hotspot/share/runtime/threadHeapSampler.cpp	Wed Sep 05 10:17:11 2018 -0700
@@ -104,8 +104,10 @@
 }
 
 void ThreadHeapSampler::pick_next_sample(size_t overflowed_bytes) {
-  if (get_sampling_interval() == 1) {
-    _bytes_until_sample = 1;
+  // Explicitly test if the sampling interval is 0, return 0 to sample every
+  // allocation.
+  if (get_sampling_interval() == 0) {
+    _bytes_until_sample = 0;
     return;
   }