7129514: time warp warnings after 7117303
Summary: Replace calls to os::javaTimeMillis() that are used to update the milliseconds since the last GC to an equivalent that uses a monotonically non-decreasing time source.
Reviewed-by: ysr, jmasa
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Tue Feb 14 08:21:08 2012 -0500
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Wed Jan 18 09:50:16 2012 -0800
@@ -6092,7 +6092,11 @@
_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
--- a/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp Tue Feb 14 08:21:08 2012 -0500
+++ b/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp Wed Jan 18 09:50:16 2012 -0800
@@ -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 @@
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();
--- a/hotspot/src/share/vm/memory/defNewGeneration.cpp Tue Feb 14 08:21:08 2012 -0500
+++ b/hotspot/src/share/vm/memory/defNewGeneration.cpp Wed Jan 18 09:50:16 2012 -0800
@@ -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 @@
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 {
--- a/hotspot/src/share/vm/memory/genMarkSweep.cpp Tue Feb 14 08:21:08 2012 -0500
+++ b/hotspot/src/share/vm/memory/genMarkSweep.cpp Wed Jan 18 09:50:16 2012 -0800
@@ -176,7 +176,11 @@
// 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() {