diff --git a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
index 986495cbeaf2b66159d2e7ef84d1c6d3cecda1b6..ac8ac93ff9e6d6ee7d72c77567bcdf81d6f0649e 100644
--- a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
+++ b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
@@ -6092,7 +6092,11 @@ void CMSCollector::sweep(bool asynch) {
   _inter_sweep_timer.reset();
   _inter_sweep_timer.start();
 
-  update_time_of_last_gc(os::javaTimeMillis());
+  // We need to use a monotonically non-deccreasing time in ms
+  // or we will see time-warp warnings and os::javaTimeMillis()
+  // does not guarantee monotonicity.
+  jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
+  update_time_of_last_gc(now);
 
   // NOTE on abstract state transitions:
   // Mutators allocate-live and/or mark the mod-union table dirty
diff --git a/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp b/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp
index 91445947c33b0126cf7cf3a044242bf8702b5988..4f64dff08243ca8d12afbfd8f73052840607c82c 100644
--- a/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp
+++ b/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1042,7 +1042,11 @@ void ParNewGeneration::collect(bool   full,
     size_policy->avg_survived()->sample(from()->used());
   }
 
-  update_time_of_last_gc(os::javaTimeMillis());
+  // We need to use a monotonically non-deccreasing time in ms
+  // or we will see time-warp warnings and os::javaTimeMillis()
+  // does not guarantee monotonicity.
+  jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
+  update_time_of_last_gc(now);
 
   SpecializationStats::print();
 
diff --git a/src/share/vm/memory/defNewGeneration.cpp b/src/share/vm/memory/defNewGeneration.cpp
index 5913b2c78f9901bf0397abff80e0743d2978df2e..69ae3624a25befc08a439f188b462ee42f34a39a 100644
--- a/src/share/vm/memory/defNewGeneration.cpp
+++ b/src/share/vm/memory/defNewGeneration.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -655,7 +655,12 @@ void DefNewGeneration::collect(bool   full,
   from()->set_concurrent_iteration_safe_limit(from()->top());
   to()->set_concurrent_iteration_safe_limit(to()->top());
   SpecializationStats::print();
-  update_time_of_last_gc(os::javaTimeMillis());
+
+  // We need to use a monotonically non-deccreasing time in ms
+  // or we will see time-warp warnings and os::javaTimeMillis()
+  // does not guarantee monotonicity.
+  jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
+  update_time_of_last_gc(now);
 }
 
 class RemoveForwardPointerClosure: public ObjectClosure {
diff --git a/src/share/vm/memory/genMarkSweep.cpp b/src/share/vm/memory/genMarkSweep.cpp
index 925d968b6bc49c9adbf5b48f9f34fbc38a2bbb97..d5cf4dc756261b24c2ee413871a8c5fba5739ca7 100644
--- a/src/share/vm/memory/genMarkSweep.cpp
+++ b/src/share/vm/memory/genMarkSweep.cpp
@@ -176,7 +176,11 @@ void GenMarkSweep::invoke_at_safepoint(int level, ReferenceProcessor* rp,
 
   // Update time of last gc for all generations we collected
   // (which curently is all the generations in the heap).
-  gch->update_time_of_last_gc(os::javaTimeMillis());
+  // We need to use a monotonically non-deccreasing time in ms
+  // or we will see time-warp warnings and os::javaTimeMillis()
+  // does not guarantee monotonicity.
+  jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
+  gch->update_time_of_last_gc(now);
 }
 
 void GenMarkSweep::allocate_stacks() {