--- old/src/share/vm/gc/shared/threadLocalAllocBuffer.cpp	2017-06-30 13:52:10.043467733 -0700
+++ new/src/share/vm/gc/shared/threadLocalAllocBuffer.cpp	2017-06-30 13:52:09.899468252 -0700
@@ -127,7 +127,8 @@
     }
   }
   assert(!(retire || ZeroTLAB)  ||
-         (start() == NULL && end() == NULL && top() == NULL),
+         (start() == NULL && end() == NULL && top() == NULL &&
+          actual_end() == NULL && slow_path_end() == NULL),
          "TLAB must be reset");
 }
 
@@ -327,12 +328,20 @@
   size_t words_until_sample = bytes_left / HeapWordSize;
 
   if (heap_words_remaining > words_until_sample) {
-    set_end(_top + words_until_sample);
+    HeapWord* new_end = _top + words_until_sample;
+    set_end(new_end);
+    set_slow_path_end(new_end);
     set_bytes_until_sample(0);
   } else {
     bytes_left -= heap_words_remaining * HeapWordSize;
     set_bytes_until_sample(bytes_left);
   }
+
+  log_trace(gc, tlab)("TLAB picked next sample: thread: " INTPTR_FORMAT " [id: %2d]"
+                      " start: %p  top: %p end: %p actual_end: %p slow_path_end: %p",
+                      p2i(myThread()), myThread()->osthread()->thread_id(),
+                      start(), top(), end(),
+                      actual_end(), slow_path_end());
 }
 
 Thread* ThreadLocalAllocBuffer::myThread() {