8145312: CMS: There is insufficient memory with CMSSamplingGrain=1
authorsangheki
Wed, 09 Mar 2016 15:37:33 -0800
changeset 37054 31d83caf01e8
parent 37053 4eac559b9503
child 37055 3ea6a0d5a78c
child 37056 109f610020fa
8145312: CMS: There is insufficient memory with CMSSamplingGrain=1 Summary: Change minimum range and add constraint function for CMSSamplingGrain flag Reviewed-by: jmasa, ddmitriev
hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.cpp
hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.hpp
hotspot/src/share/vm/runtime/globals.hpp
--- a/hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.cpp	Wed Mar 09 20:37:04 2016 +0000
+++ b/hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.cpp	Wed Mar 09 15:37:33 2016 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2016, 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
@@ -25,6 +25,7 @@
 #include "precompiled.hpp"
 #include "gc/shared/collectedHeap.hpp"
 #include "gc/shared/collectorPolicy.hpp"
+#include "gc/shared/genCollectedHeap.hpp"
 #include "gc/shared/threadLocalAllocBuffer.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/commandLineFlagConstraintsGC.hpp"
@@ -448,6 +449,22 @@
   return Flag::SUCCESS;
 }
 
+Flag::Error CMSSamplingGrainConstraintFunc(uintx value, bool verbose) {
+#if INCLUDE_ALL_GCS
+  if (UseConcMarkSweepGC) {
+    size_t max_capacity = GenCollectedHeap::heap()->young_gen()->max_capacity();
+    if (value > max_uintx - max_capacity) {
+    CommandLineError::print(verbose,
+                            "CMSSamplingGrain (" UINTX_FORMAT ") must be "
+                            "less than or equal to ergonomic maximum (" SIZE_FORMAT ")\n",
+                            value, max_uintx - max_capacity);
+    return Flag::VIOLATES_CONSTRAINT;
+    }
+  }
+#endif
+  return Flag::SUCCESS;
+}
+
 Flag::Error CMSWorkQueueDrainThresholdConstraintFunc(uintx value, bool verbose) {
 #if INCLUDE_ALL_GCS
   if (UseConcMarkSweepGC) {
--- a/hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.hpp	Wed Mar 09 20:37:04 2016 +0000
+++ b/hotspot/src/share/vm/runtime/commandLineFlagConstraintsGC.hpp	Wed Mar 09 15:37:33 2016 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2016, 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
@@ -61,6 +61,7 @@
 Flag::Error MarkStackSizeConstraintFunc(size_t value, bool verbose);
 Flag::Error CMSPrecleanDenominatorConstraintFunc(uintx value, bool verbose);
 Flag::Error CMSPrecleanNumeratorConstraintFunc(uintx value, bool verbose);
+Flag::Error CMSSamplingGrainConstraintFunc(uintx value, bool verbose);
 Flag::Error CMSWorkQueueDrainThresholdConstraintFunc(uintx value, bool verbose);
 Flag::Error MaxGCPauseMillisConstraintFunc(uintx value, bool verbose);
 Flag::Error GCPauseIntervalMillisConstraintFunc(uintx value, bool verbose);
--- a/hotspot/src/share/vm/runtime/globals.hpp	Wed Mar 09 20:37:04 2016 +0000
+++ b/hotspot/src/share/vm/runtime/globals.hpp	Wed Mar 09 15:37:33 2016 -0800
@@ -1901,7 +1901,8 @@
                                                                             \
   product(uintx, CMSSamplingGrain, 16*K,                                    \
           "The minimum distance between eden samples for CMS (see above)")  \
-          range(1, max_uintx)                                               \
+          range(ObjectAlignmentInBytes, max_uintx)                          \
+          constraint(CMSSamplingGrainConstraintFunc,AfterMemoryInit)        \
                                                                             \
   product(bool, CMSScavengeBeforeRemark, false,                             \
           "Attempt scavenge before the CMS remark step")                    \