jdk-sandbox: comparison src/hotspot/share/memory/metaspace.hpp

equal deleted inserted replaced

-:b70281f5146e
+:57dd7b4ba338
 class PrintCLDMetaspaceInfoClosure;
 class SpaceManager;
 class VirtualSpaceList;
 class CollectedHeap;
+namespace metaspace {
+namespace internals {
+class ClassLoaderMetaspaceStatistics;
+}}
 // Metaspaces each have a  SpaceManager and allocations
 // are done by the SpaceManager.  Allocations are done
 // out of the current Metachunk.  When the current Metachunk
 // is exhausted, the SpaceManager gets a new one from
 // the current VirtualSpace.  When the VirtualSpace is exhausted
 ClassType,
 NonClassType,
 MetadataTypeCount
 };
 enum MetaspaceType {
-StandardMetaspaceType,
+ZeroMetaspaceType = 0,
-BootMetaspaceType,
+StandardMetaspaceType = ZeroMetaspaceType,
-AnonymousMetaspaceType,
+BootMetaspaceType = StandardMetaspaceType + 1,
-ReflectionMetaspaceType
+AnonymousMetaspaceType = BootMetaspaceType + 1,
+ReflectionMetaspaceType = AnonymousMetaspaceType + 1,
+MetaspaceTypeCount
 };
 private:
 // Align up the word size to the allocation word size
 static size_t commit_alignment()        { return _commit_alignment; }
 static size_t commit_alignment_words()  { return _commit_alignment / BytesPerWord; }
 static MetaWord* allocate(ClassLoaderData* loader_data, size_t word_size,
 MetaspaceObj::Type type, TRAPS);
-void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
 static bool contains(const void* ptr);
 static bool contains_non_shared(const void* ptr);
 // Free empty virtualspaces
 // special cases such as the boot class loader, reflection
 // class loader and anonymous class loader.
 void initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
 Metachunk* get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
+const Metaspace::MetaspaceType _space_type;
+Mutex* const  _lock;
 SpaceManager* _vsm;
+SpaceManager* _class_vsm;
 SpaceManager* vsm() const { return _vsm; }
-SpaceManager* _class_vsm;
 SpaceManager* class_vsm() const { return _class_vsm; }
 SpaceManager* get_space_manager(Metaspace::MetadataType mdtype) {
 assert(mdtype != Metaspace::MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
 return mdtype == Metaspace::ClassType ? class_vsm() : vsm();
 }
+Mutex* lock() const { return _lock; }
 MetaWord* expand_and_allocate(size_t size, Metaspace::MetadataType mdtype);
 size_t class_chunk_size(size_t word_size);
+// Adds to the given statistic object. Must be locked with CLD metaspace lock.
+void add_to_statistics_locked(metaspace::internals::ClassLoaderMetaspaceStatistics* out) const;
 public:
 ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type);
 ~ClassLoaderMetaspace();
+Metaspace::MetaspaceType space_type() const { return _space_type; }
 // Allocate space for metadata of type mdtype. This is space
 // within a Metachunk and is used by
 //   allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)
 MetaWord* allocate(size_t word_size, Metaspace::MetadataType mdtype);
-size_t used_words_slow(Metaspace::MetadataType mdtype) const;
-size_t free_words_slow(Metaspace::MetadataType mdtype) const;
-size_t capacity_words_slow(Metaspace::MetadataType mdtype) const;
-size_t used_bytes_slow(Metaspace::MetadataType mdtype) const;
-size_t capacity_bytes_slow(Metaspace::MetadataType mdtype) const;
 size_t allocated_blocks_bytes() const;
 size_t allocated_chunks_bytes() const;
 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
-void dump(outputStream* const out) const;
 void print_on(outputStream* st) const;
 // Debugging support
 void verify();
+// Adds to the given statistic object. Will lock with CLD metaspace lock.
+void add_to_statistics(metaspace::internals::ClassLoaderMetaspaceStatistics* out) const;
 }; // ClassLoaderMetaspace
 class MetaspaceUtils : AllStatic {
+// Spacemanager updates running counters.
+friend class SpaceManager;
+// Running counters for statistics concerning in-use chunks.
+// Note: capacity = used + free + waste + overhead. Note that we do not
+// count free and waste. Their sum can be deduces from the three other values.
+// For more details, one should call print_report() from within a safe point.
+static size_t _capacity_words [Metaspace:: MetadataTypeCount];
+static size_t _overhead_words [Metaspace:: MetadataTypeCount];
+static volatile size_t _used_words [Metaspace:: MetadataTypeCount];
+// Atomically decrement or increment in-use statistic counters
+static void dec_capacity(Metaspace::MetadataType mdtype, size_t words);
+static void inc_capacity(Metaspace::MetadataType mdtype, size_t words);
+static void dec_used(Metaspace::MetadataType mdtype, size_t words);
+static void inc_used(Metaspace::MetadataType mdtype, size_t words);
+static void dec_overhead(Metaspace::MetadataType mdtype, size_t words);
+static void inc_overhead(Metaspace::MetadataType mdtype, size_t words);
+// Getters for the in-use counters.
+static size_t capacity_words(Metaspace::MetadataType mdtype)        { return _capacity_words[mdtype]; }
+static size_t used_words(Metaspace::MetadataType mdtype)            { return _used_words[mdtype]; }
+static size_t overhead_words(Metaspace::MetadataType mdtype)        { return _overhead_words[mdtype]; }
 static size_t free_chunks_total_words(Metaspace::MetadataType mdtype);
-// These methods iterate over the classloader data graph
+// Helper for print_xx_report.
-// for the given Metaspace type.  These are slow.
+static void print_vs(outputStream* out, size_t scale);
-static size_t used_bytes_slow(Metaspace::MetadataType mdtype);
-static size_t free_bytes_slow(Metaspace::MetadataType mdtype);
+public:
-static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);
-static size_t capacity_bytes_slow();
+// Collect used metaspace statistics. This involves walking the CLDG. The resulting
+// output will be the accumulated values for all live metaspaces.
-// Running sum of space in all Metachunks that has been
+// Note: method does not do any locking.
-// allocated to a Metaspace.  This is used instead of
+static void collect_statistics(metaspace::internals::ClassLoaderMetaspaceStatistics* out);
-// iterating over all the classloaders. One for each
-// type of Metadata
-static size_t _capacity_words[Metaspace:: MetadataTypeCount];
-// Running sum of space in all Metachunks that
-// are being used for metadata. One for each
-// type of Metadata.
-static volatile size_t _used_words[Metaspace:: MetadataTypeCount];
-public:
-// Decrement and increment _allocated_capacity_words
-static void dec_capacity(Metaspace::MetadataType type, size_t words);
-static void inc_capacity(Metaspace::MetadataType type, size_t words);
-// Decrement and increment _allocated_used_words
-static void dec_used(Metaspace::MetadataType type, size_t words);
-static void inc_used(Metaspace::MetadataType type, size_t words);
-// Total of space allocated to metadata in all Metaspaces.
-// This sums the space used in each Metachunk by
-// iterating over the classloader data graph
-static size_t used_bytes_slow() {
-return used_bytes_slow(Metaspace::ClassType) +
-used_bytes_slow(Metaspace::NonClassType);
-}
 // Used by MetaspaceCounters
 static size_t free_chunks_total_words();
 static size_t free_chunks_total_bytes();
 static size_t free_chunks_total_bytes(Metaspace::MetadataType mdtype);
-static size_t capacity_words(Metaspace::MetadataType mdtype) {
-return _capacity_words[mdtype];
-}
 static size_t capacity_words() {
 return capacity_words(Metaspace::NonClassType) +
 capacity_words(Metaspace::ClassType);
 }
 static size_t capacity_bytes(Metaspace::MetadataType mdtype) {
 }
 static size_t capacity_bytes() {
 return capacity_words() * BytesPerWord;
 }
-static size_t used_words(Metaspace::MetadataType mdtype) {
-return _used_words[mdtype];
-}
 static size_t used_words() {
 return used_words(Metaspace::NonClassType) +
 used_words(Metaspace::ClassType);
 }
 static size_t used_bytes(Metaspace::MetadataType mdtype) {
 }
 static size_t used_bytes() {
 return used_words() * BytesPerWord;
 }
-static size_t free_bytes();
+// Space committed but yet unclaimed by any class loader.
-static size_t free_bytes(Metaspace::MetadataType mdtype);
+static size_t free_in_vs_bytes();
+static size_t free_in_vs_bytes(Metaspace::MetadataType mdtype);
 static size_t reserved_bytes(Metaspace::MetadataType mdtype);
 static size_t reserved_bytes() {
 return reserved_bytes(Metaspace::ClassType) +
 reserved_bytes(Metaspace::NonClassType);
 static size_t min_chunk_size_words();
 static size_t min_chunk_size_bytes() {
 return min_chunk_size_words() * BytesPerWord;
 }
-static void print_metadata_for_nmt(outputStream* out, size_t scale = K);
+// Flags for print_report().
+enum ReportFlag {
+// Show usage by class loader.
+rf_show_loaders                 = (1 << 0),
+// Breaks report down by chunk type (small, medium, ...).
+rf_break_down_by_chunktype      = (1 << 1),
+// Breaks report down by space type (anonymous, reflection, ...).
+rf_break_down_by_spacetype      = (1 << 2),
+// Print details about the underlying virtual spaces.
+rf_show_vslist                  = (1 << 3),
+// Print metaspace map.
+rf_show_vsmap                   = (1 << 4)
+};
+// This will print out a basic metaspace usage report but
+// unlike print_report() is guaranteed not to lock or to walk the CLDG.
+static void print_basic_report(outputStream* st, size_t scale);
+// Prints a report about the current metaspace state.
+// Optional parts can be enabled via flags.
+// Function will walk the CLDG and will lock the expand lock; if that is not
+// convenient, use print_basic_report() instead.
+static void print_report(outputStream* out, size_t scale = 0, int flags = 0);
 static bool has_chunk_free_list(Metaspace::MetadataType mdtype);
 static MetaspaceChunkFreeListSummary chunk_free_list_summary(Metaspace::MetadataType mdtype);
 // Print change in used metadata.
 static void print_metaspace_change(size_t prev_metadata_used);
 static void print_on(outputStream * out);
-static void print_on(outputStream * out, Metaspace::MetadataType mdtype);
-static void print_class_waste(outputStream* out);
-static void print_waste(outputStream* out);
 // Prints an ASCII representation of the given space.
 static void print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype);
 static void dump(outputStream* out);
 static void verify_free_chunks();
-// Checks that the values returned by allocated_capacity_bytes() and
+// Check internal counters (capacity, used).
-// capacity_bytes_slow() are the same.
-static void verify_capacity();
-static void verify_used();
 static void verify_metrics();
 };
 // Metaspace are deallocated when their class loader are GC'ed.
 // This class implements a policy for inducing GC's to recover

changeset 49980	57dd7b4ba338
parent 49449	ef5d5d343e2a
child 50119	bf9177eac58d