8024547: MaxMetaspaceSize should limit the committed memory used by the metaspaces

Reviewed-by: brutisso, jmasa, coleenp

src/share/vm/gc_implementation/shared/vmGCOperations.hpp

@@ -214,9 +214,6 @@ class VM_CollectForMetadataAllocation: public VM_GC_Operation {
     : VM_GC_Operation(gc_count_before, gc_cause, full_gc_count_before, true),
       _loader_data(loader_data), _size(size), _mdtype(mdtype), _result(NULL) {
   }
-  ~VM_CollectForMetadataAllocation()  {
-    MetaspaceGC::set_expand_after_GC(false);
-  }
   virtual VMOp_Type type() const { return VMOp_CollectForMetadataAllocation; }
   virtual void doit();
   MetaWord* result() const       { return _result; }

src/share/vm/gc_interface/collectedHeap.cpp

@@ -202,12 +202,6 @@ void CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
       ShouldNotReachHere(); // Unexpected use of this function
   }
 }
-MetaWord* CollectedHeap::satisfy_failed_metadata_allocation(
-                                              ClassLoaderData* loader_data,
-                                              size_t size, Metaspace::MetadataType mdtype) {
-  return collector_policy()->satisfy_failed_metadata_allocation(loader_data, size, mdtype);
-}
-
 
 void CollectedHeap::pre_initialize() {
   // Used for ReduceInitialCardMarks (when COMPILER2 is used);

src/share/vm/gc_interface/collectedHeap.hpp

@@ -475,11 +475,6 @@ class CollectedHeap : public CHeapObj<mtInternal> {
   // the context of the vm thread.
   virtual void collect_as_vm_thread(GCCause::Cause cause);
 
-  // Callback from VM_CollectForMetadataAllocation operation.
-  MetaWord* satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
-                                               size_t size,
-                                               Metaspace::MetadataType mdtype);
-
   // Returns the barrier set for this heap
   BarrierSet* barrier_set() { return _barrier_set; }
 

src/share/vm/memory/collectorPolicy.cpp

@@ -47,11 +47,6 @@
 
 // CollectorPolicy methods.
 
-// Align down. If the aligning result in 0, return 'alignment'.
-static size_t restricted_align_down(size_t size, size_t alignment) {
-  return MAX2(alignment, align_size_down_(size, alignment));
-}
-
 void CollectorPolicy::initialize_flags() {
   assert(_max_alignment >= _min_alignment,
          err_msg("max_alignment: " SIZE_FORMAT " less than min_alignment: " SIZE_FORMAT,
@@ -64,34 +59,7 @@ void CollectorPolicy::initialize_flags() {
     vm_exit_during_initialization("Incompatible initial and maximum heap sizes specified");
   }
 
-  // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
-  // override if MaxMetaspaceSize was set on the command line or not.
-  // This information is needed later to conform to the specification of the
-  // java.lang.management.MemoryUsage API.
-  //
-  // Ideally, we would be able to set the default value of MaxMetaspaceSize in
-  // globals.hpp to the aligned value, but this is not possible, since the
-  // alignment depends on other flags being parsed.
-  MaxMetaspaceSize = restricted_align_down(MaxMetaspaceSize, _max_alignment);
-
-  if (MetaspaceSize > MaxMetaspaceSize) {
-    MetaspaceSize = MaxMetaspaceSize;
-  }
-
-  MetaspaceSize = restricted_align_down(MetaspaceSize, _min_alignment);
-
-  assert(MetaspaceSize <= MaxMetaspaceSize, "Must be");
-
-  MinMetaspaceExpansion = restricted_align_down(MinMetaspaceExpansion, _min_alignment);
-  MaxMetaspaceExpansion = restricted_align_down(MaxMetaspaceExpansion, _min_alignment);
-
   MinHeapDeltaBytes = align_size_up(MinHeapDeltaBytes, _min_alignment);
-
-  assert(MetaspaceSize    % _min_alignment == 0, "metapace alignment");
-  assert(MaxMetaspaceSize % _max_alignment == 0, "maximum metaspace alignment");
-  if (MetaspaceSize < 256*K) {
-    vm_exit_during_initialization("Too small initial Metaspace size");
-  }
 }
 
 void CollectorPolicy::initialize_size_info() {

src/share/vm/memory/filemap.hpp

@@ -26,6 +26,7 @@
 #define SHARE_VM_MEMORY_FILEMAP_HPP
 
 #include "memory/metaspaceShared.hpp"
+#include "memory/metaspace.hpp"
 
 // Layout of the file:
 //  header: dump of archive instance plus versioning info, datestamp, etc.

src/share/vm/memory/metaspace.hpp

@@ -87,9 +87,10 @@ class Metaspace : public CHeapObj<mtClass> {
   friend class MetaspaceAux;
 
  public:
-  enum MetadataType {ClassType = 0,
-                     NonClassType = ClassType + 1,
-                     MetadataTypeCount = ClassType + 2
+  enum MetadataType {
+    ClassType,
+    NonClassType,
+    MetadataTypeCount
   };
   enum MetaspaceType {
     StandardMetaspaceType,
@@ -103,6 +104,9 @@ class Metaspace : public CHeapObj<mtClass> {
  private:
   void initialize(Mutex* lock, MetaspaceType type);
 
+  // Get the first chunk for a Metaspace.  Used for
+  // special cases such as the boot class loader, reflection
+  // class loader and anonymous class loader.
   Metachunk* get_initialization_chunk(MetadataType mdtype,
                                       size_t chunk_word_size,
                                       size_t chunk_bunch);
@@ -123,6 +127,9 @@ class Metaspace : public CHeapObj<mtClass> {
   static size_t _first_chunk_word_size;
   static size_t _first_class_chunk_word_size;
 
+  static size_t _commit_alignment;
+  static size_t _reserve_alignment;
+
   SpaceManager* _vsm;
   SpaceManager* vsm() const { return _vsm; }
 
@@ -191,12 +198,17 @@ class Metaspace : public CHeapObj<mtClass> {
   Metaspace(Mutex* lock, MetaspaceType type);
   ~Metaspace();
 
-  // Initialize globals for Metaspace
+  static void ergo_initialize();
   static void global_initialize();
 
   static size_t first_chunk_word_size() { return _first_chunk_word_size; }
   static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }
 
+  static size_t reserve_alignment()       { return _reserve_alignment; }
+  static size_t reserve_alignment_words() { return _reserve_alignment / BytesPerWord; }
+  static size_t commit_alignment()        { return _commit_alignment; }
+  static size_t commit_alignment_words()  { return _commit_alignment / BytesPerWord; }
+
   char*  bottom() const;
   size_t used_words_slow(MetadataType mdtype) const;
   size_t free_words_slow(MetadataType mdtype) const;
@@ -219,6 +231,9 @@ class Metaspace : public CHeapObj<mtClass> {
   static void purge(MetadataType mdtype);
   static void purge();
 
+  static void report_metadata_oome(ClassLoaderData* loader_data, size_t word_size,
+                                   MetadataType mdtype, TRAPS);
+
   void print_on(outputStream* st) const;
   // Debugging support
   void verify();
@@ -352,17 +367,10 @@ class MetaspaceAux : AllStatic {
 
 class MetaspaceGC : AllStatic {
 
-  // The current high-water-mark for inducing a GC.  When
-  // the capacity of all space in the virtual lists reaches this value,
-  // a GC is induced and the value is increased.  This should be changed
-  // to the space actually used for allocations to avoid affects of
-  // fragmentation losses to partially used chunks.  Size is in words.
-  static size_t _capacity_until_GC;
-
-  // After a GC is done any allocation that fails should try to expand
-  // the capacity of the Metaspaces.  This flag is set during attempts
-  // to allocate in the VMGCOperation that does the GC.
-  static bool _expand_after_GC;
+  // The current high-water-mark for inducing a GC.
+  // When committed memory of all metaspaces reaches this value,
+  // a GC is induced and the value is increased. Size is in bytes.
+  static volatile intptr_t _capacity_until_GC;
 
   // For a CMS collection, signal that a concurrent collection should
   // be started.
@@ -370,20 +378,16 @@ class MetaspaceGC : AllStatic {
 
   static uint _shrink_factor;
 
-  static void set_capacity_until_GC(size_t v) { _capacity_until_GC = v; }
-
   static size_t shrink_factor() { return _shrink_factor; }
   void set_shrink_factor(uint v) { _shrink_factor = v; }
 
  public:
 
-  static size_t capacity_until_GC() { return _capacity_until_GC; }
-  static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; }
-  static void dec_capacity_until_GC(size_t v) {
-    _capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0;
-  }
-  static bool expand_after_GC()           { return _expand_after_GC; }
-  static void set_expand_after_GC(bool v) { _expand_after_GC = v; }
+  static void initialize() { _capacity_until_GC = MetaspaceSize; }
+
+  static size_t capacity_until_GC();
+  static size_t inc_capacity_until_GC(size_t v);
+  static size_t dec_capacity_until_GC(size_t v);
 
   static bool should_concurrent_collect() { return _should_concurrent_collect; }
   static void set_should_concurrent_collect(bool v) {
@@ -391,11 +395,14 @@ class MetaspaceGC : AllStatic {
   }
 
   // The amount to increase the high-water-mark (_capacity_until_GC)
-  static size_t delta_capacity_until_GC(size_t word_size);
+  static size_t delta_capacity_until_GC(size_t bytes);
+
+  // Tells if we have can expand metaspace without hitting set limits.
+  static bool can_expand(size_t words, bool is_class);
 
-  // It is expected that this will be called when the current capacity
-  // has been used and a GC should be considered.
-  static bool should_expand(VirtualSpaceList* vsl, size_t word_size);
+  // Returns amount that we can expand without hitting a GC,
+  // measured in words.
+  static size_t allowed_expansion();
 
   // Calculate the new high-water mark at which to induce
   // a GC.

src/share/vm/runtime/arguments.cpp

@@ -3656,6 +3656,9 @@ jint Arguments::apply_ergo() {
   assert(verify_serial_gc_flags(), "SerialGC unset");
 #endif // INCLUDE_ALL_GCS
 
+  // Initialize Metaspace flags and alignments.
+  Metaspace::ergo_initialize();
+
   // Set bytecode rewriting flags
   set_bytecode_flags();
 

src/share/vm/runtime/globals.hpp

@@ -502,6 +502,10 @@ class CommandLineFlags {
   develop(bool, LargePagesIndividualAllocationInjectError, false,           \
           "Fail large pages individual allocation")                         \
                                                                             \
+  product(bool, UseLargePagesInMetaspace, false,                            \
+          "Use large page memory in metaspace. "                            \
+          "Only used if UseLargePages is enabled.")                         \
+                                                                            \
   develop(bool, TracePageSizes, false,                                      \
           "Trace page size selection and usage")                            \
                                                                             \