--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/memory/metaspace.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,418 @@
+/*
+ * Copyright (c) 2011, 2017, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+#ifndef SHARE_VM_MEMORY_METASPACE_HPP
+#define SHARE_VM_MEMORY_METASPACE_HPP
+
+#include "memory/allocation.hpp"
+#include "memory/memRegion.hpp"
+#include "memory/metaspaceChunkFreeListSummary.hpp"
+#include "memory/virtualspace.hpp"
+#include "utilities/exceptions.hpp"
+
+// Metaspace
+//
+// Metaspaces are Arenas for the VM's metadata.
+// They are allocated one per class loader object, and one for the null
+// bootstrap class loader
+//
+// block X ---+ +-------------------+
+// | | Virtualspace |
+// | | |
+// | | |
+// | |-------------------|
+// | || Chunk |
+// | || |
+// | ||---------- |
+// +------>||| block 0 | |
+// ||---------- |
+// ||| block 1 | |
+// ||---------- |
+// || |
+// |-------------------|
+// | |
+// | |
+// +-------------------+
+//
+
+class ChunkManager;
+class ClassLoaderData;
+class Metablock;
+class Metachunk;
+class MetaspaceTracer;
+class MetaWord;
+class Mutex;
+class outputStream;
+class SpaceManager;
+class VirtualSpaceList;
+
+// 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
+// the SpaceManager gets a new one. The SpaceManager
+// also manages freelists of available Chunks.
+//
+// Currently the space manager maintains the list of
+// virtual spaces and the list of chunks in use. Its
+// allocate() method returns a block for use as a
+// quantum of metadata.
+
+class Metaspace : public CHeapObj<mtClass> {
+ friend class VMStructs;
+ friend class SpaceManager;
+ friend class VM_CollectForMetadataAllocation;
+ friend class MetaspaceGC;
+ friend class MetaspaceAux;
+ friend class MetaspaceShared;
+ friend class CollectorPolicy;
+
+ public:
+ enum MetadataType {
+ ClassType,
+ NonClassType,
+ MetadataTypeCount
+ };
+ enum MetaspaceType {
+ StandardMetaspaceType,
+ BootMetaspaceType,
+ AnonymousMetaspaceType,
+ ReflectionMetaspaceType
+ };
+
+ private:
+ static void verify_global_initialization();
+
+ void initialize(Mutex* lock, MetaspaceType type);
+
+ // Initialize the first chunk for a Metaspace. Used for
+ // special cases such as the boot class loader, reflection
+ // class loader and anonymous class loader.
+ void initialize_first_chunk(MetaspaceType type, MetadataType mdtype);
+ Metachunk* get_initialization_chunk(MetaspaceType type, MetadataType mdtype);
+
+ // Align up the word size to the allocation word size
+ static size_t align_word_size_up(size_t);
+
+ // Aligned size of the metaspace.
+ static size_t _compressed_class_space_size;
+
+ static size_t compressed_class_space_size() {
+ return _compressed_class_space_size;
+ }
+
+ static void set_compressed_class_space_size(size_t size) {
+ _compressed_class_space_size = size;
+ }
+
+ 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;
+ DEBUG_ONLY(static bool _frozen;)
+
+ SpaceManager* _vsm;
+ SpaceManager* vsm() const { return _vsm; }
+
+ SpaceManager* _class_vsm;
+ SpaceManager* class_vsm() const { return _class_vsm; }
+ SpaceManager* get_space_manager(MetadataType mdtype) {
+ assert(mdtype != MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
+ return mdtype == ClassType ? class_vsm() : vsm();
+ }
+
+ // 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, MetadataType mdtype);
+
+ MetaWord* expand_and_allocate(size_t size, MetadataType mdtype);
+
+ // Virtual Space lists for both classes and other metadata
+ static VirtualSpaceList* _space_list;
+ static VirtualSpaceList* _class_space_list;
+
+ static ChunkManager* _chunk_manager_metadata;
+ static ChunkManager* _chunk_manager_class;
+
+ static const MetaspaceTracer* _tracer;
+
+ public:
+ static VirtualSpaceList* space_list() { return _space_list; }
+ static VirtualSpaceList* class_space_list() { return _class_space_list; }
+ static VirtualSpaceList* get_space_list(MetadataType mdtype) {
+ assert(mdtype != MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
+ return mdtype == ClassType ? class_space_list() : space_list();
+ }
+
+ static ChunkManager* chunk_manager_metadata() { return _chunk_manager_metadata; }
+ static ChunkManager* chunk_manager_class() { return _chunk_manager_class; }
+ static ChunkManager* get_chunk_manager(MetadataType mdtype) {
+ assert(mdtype != MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
+ return mdtype == ClassType ? chunk_manager_class() : chunk_manager_metadata();
+ }
+
+ static const MetaspaceTracer* tracer() { return _tracer; }
+ static void freeze() {
+ assert(DumpSharedSpaces, "sanity");
+ DEBUG_ONLY(_frozen = true;)
+ }
+ private:
+
+#ifdef _LP64
+ static void set_narrow_klass_base_and_shift(address metaspace_base, address cds_base);
+
+ // Returns true if can use CDS with metaspace allocated as specified address.
+ static bool can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base);
+
+ static void allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base);
+
+ static void initialize_class_space(ReservedSpace rs);
+#endif
+ size_t class_chunk_size(size_t word_size);
+
+ public:
+
+ Metaspace(Mutex* lock, MetaspaceType type);
+ ~Metaspace();
+
+ static void ergo_initialize();
+ static void global_initialize();
+ static void post_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; }
+
+ size_t used_words_slow(MetadataType mdtype) const;
+ size_t free_words_slow(MetadataType mdtype) const;
+ size_t capacity_words_slow(MetadataType mdtype) const;
+
+ size_t used_bytes_slow(MetadataType mdtype) const;
+ size_t capacity_bytes_slow(MetadataType mdtype) const;
+
+ size_t allocated_blocks_bytes() const;
+ size_t allocated_chunks_bytes() const;
+
+ 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);
+
+ void dump(outputStream* const out) const;
+
+ // Free empty virtualspaces
+ static void purge(MetadataType mdtype);
+ static void purge();
+
+ static void report_metadata_oome(ClassLoaderData* loader_data, size_t word_size,
+ MetaspaceObj::Type type, MetadataType mdtype, TRAPS);
+
+ static const char* metadata_type_name(Metaspace::MetadataType mdtype);
+
+ void print_on(outputStream* st) const;
+ // Debugging support
+ void verify();
+
+ static void print_compressed_class_space(outputStream* st, const char* requested_addr = 0) NOT_LP64({});
+
+ // Return TRUE only if UseCompressedClassPointers is True.
+ static bool using_class_space() {
+ return NOT_LP64(false) LP64_ONLY(UseCompressedClassPointers);
+ }
+
+ static bool is_class_space_allocation(MetadataType mdType) {
+ return mdType == ClassType && using_class_space();
+ }
+
+};
+
+class MetaspaceAux : AllStatic {
+ static size_t free_chunks_total_words(Metaspace::MetadataType mdtype);
+
+ // These methods iterate over the classloader data graph
+ // for the given Metaspace type. These are slow.
+ static size_t used_bytes_slow(Metaspace::MetadataType mdtype);
+ static size_t free_bytes_slow(Metaspace::MetadataType mdtype);
+ static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);
+ static size_t capacity_bytes_slow();
+
+ // Running sum of space in all Metachunks that has been
+ // allocated to a Metaspace. This is used instead of
+ // 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 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) {
+ return capacity_words(mdtype) * BytesPerWord;
+ }
+ 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) {
+ return used_words(mdtype) * BytesPerWord;
+ }
+ static size_t used_bytes() {
+ return used_words() * BytesPerWord;
+ }
+
+ static size_t free_bytes();
+ static size_t free_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 committed_bytes(Metaspace::MetadataType mdtype);
+ static size_t committed_bytes() {
+ return committed_bytes(Metaspace::ClassType) +
+ committed_bytes(Metaspace::NonClassType);
+ }
+
+ static size_t min_chunk_size_words();
+ static size_t min_chunk_size_bytes() {
+ return min_chunk_size_words() * BytesPerWord;
+ }
+
+ 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);
+ static void dump(outputStream* out);
+ static void verify_free_chunks();
+ // Checks that the values returned by allocated_capacity_bytes() and
+ // 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
+// Metaspaces.
+
+class MetaspaceGC : AllStatic {
+
+ // 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.
+ static bool _should_concurrent_collect;
+
+ static uint _shrink_factor;
+
+ static size_t shrink_factor() { return _shrink_factor; }
+ void set_shrink_factor(uint v) { _shrink_factor = v; }
+
+ public:
+
+ static void initialize();
+ static void post_initialize();
+
+ static size_t capacity_until_GC();
+ static bool inc_capacity_until_GC(size_t v,
+ size_t* new_cap_until_GC = NULL,
+ size_t* old_cap_until_GC = NULL);
+ 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) {
+ _should_concurrent_collect = v;
+ }
+
+ // The amount to increase the high-water-mark (_capacity_until_GC)
+ 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);
+
+ // 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.
+ static void compute_new_size();
+};
+
+#endif // SHARE_VM_MEMORY_METASPACE_HPP