jdk8-mips64-public/hotspot: src/share/vm/memory/metaspace.hpp@740e263c80c6

8003424: Enable Class Data Sharing for CompressedOops
8016729: ObjectAlignmentInBytes=16 now forces the use of heap based compressed oops
8005933: The -Xshare:auto option is ignored for -server
Summary: Move klass metaspace above the heap and support CDS with compressed klass ptrs.
Reviewed-by: coleenp, kvn, mgerdin, tschatzl, stefank

     1 /*

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     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

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    23  */

    24 #ifndef SHARE_VM_MEMORY_METASPACE_HPP

    25 #define SHARE_VM_MEMORY_METASPACE_HPP

    27 #include "memory/allocation.hpp"

    28 #include "memory/memRegion.hpp"

    29 #include "runtime/virtualspace.hpp"

    30 #include "utilities/exceptions.hpp"

    32 // Metaspace

    33 //

    34 // Metaspaces are Arenas for the VM's metadata.

    35 // They are allocated one per class loader object, and one for the null

    36 // bootstrap class loader

    37 // Eventually for bootstrap loader we'll have a read-only section and read-write

    38 // to write for DumpSharedSpaces and read for UseSharedSpaces

    39 //

    40 //    block X ---+       +-------------------+

    41 //               |       |  Virtualspace     |

    42 //               |       |                   |

    43 //               |       |                   |

    44 //               |       |-------------------|

    45 //               |       || Chunk            |

    46 //               |       ||                  |

    47 //               |       ||----------        |

    48 //               +------>||| block 0 |       |

    49 //                       ||----------        |

    50 //                       ||| block 1 |       |

    51 //                       ||----------        |

    52 //                       ||                  |

    53 //                       |-------------------|

    54 //                       |                   |

    55 //                       |                   |

    56 //                       +-------------------+

    57 //

    59 class ClassLoaderData;

    60 class Metablock;

    61 class MetaWord;

    62 class Mutex;

    63 class outputStream;

    64 class SpaceManager;

    66 // Metaspaces each have a  SpaceManager and allocations

    67 // are done by the SpaceManager.  Allocations are done

    68 // out of the current Metachunk.  When the current Metachunk

    69 // is exhausted, the SpaceManager gets a new one from

    70 // the current VirtualSpace.  When the VirtualSpace is exhausted

    71 // the SpaceManager gets a new one.  The SpaceManager

    72 // also manages freelists of available Chunks.

    73 //

    74 // Currently the space manager maintains the list of

    75 // virtual spaces and the list of chunks in use.  Its

    76 // allocate() method returns a block for use as a

    77 // quantum of metadata.

    79 class VirtualSpaceList;

    81 class Metaspace : public CHeapObj<mtClass> {

    82   friend class VMStructs;

    83   friend class SpaceManager;

    84   friend class VM_CollectForMetadataAllocation;

    85   friend class MetaspaceGC;

    86   friend class MetaspaceAux;

    88  public:

    89   enum MetadataType {ClassType = 0,

    90                      NonClassType = ClassType + 1,

    91                      MetadataTypeCount = ClassType + 2

    92   };

    93   enum MetaspaceType {

    94     StandardMetaspaceType,

    95     BootMetaspaceType,

    96     ROMetaspaceType,

    97     ReadWriteMetaspaceType,

    98     AnonymousMetaspaceType,

    99     ReflectionMetaspaceType

   100   };

   102  private:

   103   void initialize(Mutex* lock, MetaspaceType type);

   105   // Align up the word size to the allocation word size

   106   static size_t align_word_size_up(size_t);

   108   // Aligned size of the metaspace.

   109   static size_t _class_metaspace_size;

   111   static size_t class_metaspace_size() {

   112     return _class_metaspace_size;

   113   }

   114   static void set_class_metaspace_size(size_t metaspace_size) {

   115     _class_metaspace_size = metaspace_size;

   116   }

   118   static size_t _first_chunk_word_size;

   119   static size_t _first_class_chunk_word_size;

   121   SpaceManager* _vsm;

   122   SpaceManager* vsm() const { return _vsm; }

   124   SpaceManager* _class_vsm;

   125   SpaceManager* class_vsm() const { return _class_vsm; }

   127   // Allocate space for metadata of type mdtype. This is space

   128   // within a Metachunk and is used by

   129   //   allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)

   130   // which returns a Metablock.

   131   MetaWord* allocate(size_t word_size, MetadataType mdtype);

   133   // Virtual Space lists for both classes and other metadata

   134   static VirtualSpaceList* _space_list;

   135   static VirtualSpaceList* _class_space_list;

   137   static VirtualSpaceList* space_list()       { return _space_list; }

   138   static VirtualSpaceList* class_space_list() { return _class_space_list; }

   140   // This is used by DumpSharedSpaces only, where only _vsm is used. So we will

   141   // maintain a single list for now.

   142   void record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size);

   144 #ifdef _LP64

   145   static void set_narrow_klass_base_and_shift(address metaspace_base, address cds_base);

   147   // Returns true if can use CDS with metaspace allocated as specified address.

   148   static bool can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base);

   150   static void allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base);

   152   static void initialize_class_space(ReservedSpace rs);

   153 #endif

   155   class AllocRecord : public CHeapObj<mtClass> {

   156   public:

   157     AllocRecord(address ptr, MetaspaceObj::Type type, int byte_size)

   158       : _next(NULL), _ptr(ptr), _type(type), _byte_size(byte_size) {}

   159     AllocRecord *_next;

   160     address _ptr;

   161     MetaspaceObj::Type _type;

   162     int _byte_size;

   163   };

   165   AllocRecord * _alloc_record_head;

   166   AllocRecord * _alloc_record_tail;

   168  public:

   170   Metaspace(Mutex* lock, MetaspaceType type);

   171   ~Metaspace();

   173   // Initialize globals for Metaspace

   174   static void global_initialize();

   176   static size_t first_chunk_word_size() { return _first_chunk_word_size; }

   177   static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }

   179   char*  bottom() const;

   180   size_t used_words_slow(MetadataType mdtype) const;

   181   size_t free_words(MetadataType mdtype) const;

   182   size_t capacity_words_slow(MetadataType mdtype) const;

   183   size_t waste_words(MetadataType mdtype) const;

   185   size_t used_bytes_slow(MetadataType mdtype) const;

   186   size_t capacity_bytes_slow(MetadataType mdtype) const;

   188   static Metablock* allocate(ClassLoaderData* loader_data, size_t word_size,

   189                              bool read_only, MetaspaceObj::Type type, TRAPS);

   190   void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);

   192   MetaWord* expand_and_allocate(size_t size,

   193                                 MetadataType mdtype);

   195   static bool contains(const void *ptr);

   196   void dump(outputStream* const out) const;

   198   // Free empty virtualspaces

   199   static void purge();

   201   void print_on(outputStream* st) const;

   202   // Debugging support

   203   void verify();

   205   class AllocRecordClosure :  public StackObj {

   206   public:

   207     virtual void doit(address ptr, MetaspaceObj::Type type, int byte_size) = 0;

   208   };

   210   void iterate(AllocRecordClosure *closure);

   212   // Return TRUE only if UseCompressedKlassPointers is True and DumpSharedSpaces is False.

   213   static bool using_class_space() {

   214     return NOT_LP64(false) LP64_ONLY(UseCompressedKlassPointers && !DumpSharedSpaces);

   215   }

   217 };

   219 class MetaspaceAux : AllStatic {

   220   static size_t free_chunks_total(Metaspace::MetadataType mdtype);

   221   static size_t free_chunks_total_in_bytes(Metaspace::MetadataType mdtype);

   223  public:

   224   // Statistics for class space and data space in metaspace.

   226   // These methods iterate over the classloader data graph

   227   // for the given Metaspace type.  These are slow.

   228   static size_t used_bytes_slow(Metaspace::MetadataType mdtype);

   229   static size_t free_in_bytes(Metaspace::MetadataType mdtype);

   230   static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);

   232   // Iterates over the virtual space list.

   233   static size_t reserved_in_bytes(Metaspace::MetadataType mdtype);

   235   // Running sum of space in all Metachunks that has been

   236   // allocated to a Metaspace.  This is used instead of

   237   // iterating over all the classloaders. One for each

   238   // type of Metadata

   239   static size_t _allocated_capacity_words[Metaspace:: MetadataTypeCount];

   240   // Running sum of space in all Metachunks that have

   241   // are being used for metadata. One for each

   242   // type of Metadata.

   243   static size_t _allocated_used_words[Metaspace:: MetadataTypeCount];

   245  public:

   246   // Decrement and increment _allocated_capacity_words

   247   static void dec_capacity(Metaspace::MetadataType type, size_t words);

   248   static void inc_capacity(Metaspace::MetadataType type, size_t words);

   250   // Decrement and increment _allocated_used_words

   251   static void dec_used(Metaspace::MetadataType type, size_t words);

   252   static void inc_used(Metaspace::MetadataType type, size_t words);

   254   // Total of space allocated to metadata in all Metaspaces.

   255   // This sums the space used in each Metachunk by

   256   // iterating over the classloader data graph

   257   static size_t used_bytes_slow() {

   258     return used_bytes_slow(Metaspace::ClassType) +

   259            used_bytes_slow(Metaspace::NonClassType);

   260   }

   262   // Used by MetaspaceCounters

   263   static size_t free_chunks_total();

   264   static size_t free_chunks_total_in_bytes();

   266   static size_t allocated_capacity_words(Metaspace::MetadataType mdtype) {

   267     return _allocated_capacity_words[mdtype];

   268   }

   269   static size_t allocated_capacity_words() {

   270     return _allocated_capacity_words[Metaspace::NonClassType] +

   271            (Metaspace::using_class_space() ?

   272            _allocated_capacity_words[Metaspace::ClassType] : 0);

   273   }

   274   static size_t allocated_capacity_bytes(Metaspace::MetadataType mdtype) {

   275     return allocated_capacity_words(mdtype) * BytesPerWord;

   276   }

   277   static size_t allocated_capacity_bytes() {

   278     return allocated_capacity_words() * BytesPerWord;

   279   }

   281   static size_t allocated_used_words(Metaspace::MetadataType mdtype) {

   282     return _allocated_used_words[mdtype];

   283   }

   284   static size_t allocated_used_words() {

   285     return _allocated_used_words[Metaspace::NonClassType] +

   286            (Metaspace::using_class_space() ?

   287            _allocated_used_words[Metaspace::ClassType] : 0);

   288   }

   289   static size_t allocated_used_bytes(Metaspace::MetadataType mdtype) {

   290     return allocated_used_words(mdtype) * BytesPerWord;

   291   }

   292   static size_t allocated_used_bytes() {

   293     return allocated_used_words() * BytesPerWord;

   294   }

   296   static size_t free_bytes();

   298   // Total capacity in all Metaspaces

   299   static size_t capacity_bytes_slow() {

   300 #ifdef PRODUCT

   301     // Use allocated_capacity_bytes() in PRODUCT instead of this function.

   302     guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");

   303 #endif

   304     size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);

   305     size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);

   306     assert(allocated_capacity_bytes() == class_capacity + non_class_capacity,

   307            err_msg("bad accounting: allocated_capacity_bytes() " SIZE_FORMAT

   308              " class_capacity + non_class_capacity " SIZE_FORMAT

   309              " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,

   310              allocated_capacity_bytes(), class_capacity + non_class_capacity,

   311              class_capacity, non_class_capacity));

   313     return class_capacity + non_class_capacity;

   314   }

   316   // Total space reserved in all Metaspaces

   317   static size_t reserved_in_bytes() {

   318     return reserved_in_bytes(Metaspace::ClassType) +

   319            reserved_in_bytes(Metaspace::NonClassType);

   320   }

   322   static size_t min_chunk_size();

   324   // Print change in used metadata.

   325   static void print_metaspace_change(size_t prev_metadata_used);

   326   static void print_on(outputStream * out);

   327   static void print_on(outputStream * out, Metaspace::MetadataType mdtype);

   329   static void print_class_waste(outputStream* out);

   330   static void print_waste(outputStream* out);

   331   static void dump(outputStream* out);

   332   static void verify_free_chunks();

   333   // Checks that the values returned by allocated_capacity_bytes() and

   334   // capacity_bytes_slow() are the same.

   335   static void verify_capacity();

   336   static void verify_used();

   337   static void verify_metrics();

   338 };

   340 // Metaspace are deallocated when their class loader are GC'ed.

   341 // This class implements a policy for inducing GC's to recover

   342 // Metaspaces.

   344 class MetaspaceGC : AllStatic {

   346   // The current high-water-mark for inducing a GC.  When

   347   // the capacity of all space in the virtual lists reaches this value,

   348   // a GC is induced and the value is increased.  This should be changed

   349   // to the space actually used for allocations to avoid affects of

   350   // fragmentation losses to partially used chunks.  Size is in words.

   351   static size_t _capacity_until_GC;

   353   // After a GC is done any allocation that fails should try to expand

   354   // the capacity of the Metaspaces.  This flag is set during attempts

   355   // to allocate in the VMGCOperation that does the GC.

   356   static bool _expand_after_GC;

   358   // For a CMS collection, signal that a concurrent collection should

   359   // be started.

   360   static bool _should_concurrent_collect;

   362   static uint _shrink_factor;

   364   static void set_capacity_until_GC(size_t v) { _capacity_until_GC = v; }

   366   static size_t shrink_factor() { return _shrink_factor; }

   367   void set_shrink_factor(uint v) { _shrink_factor = v; }

   369  public:

   371   static size_t capacity_until_GC() { return _capacity_until_GC; }

   372   static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; }

   373   static void dec_capacity_until_GC(size_t v) {

   374     _capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0;

   375   }

   376   static bool expand_after_GC()           { return _expand_after_GC; }

   377   static void set_expand_after_GC(bool v) { _expand_after_GC = v; }

   379   static bool should_concurrent_collect() { return _should_concurrent_collect; }

   380   static void set_should_concurrent_collect(bool v) {

   381     _should_concurrent_collect = v;

   382   }

   384   // The amount to increase the high-water-mark (_capacity_until_GC)

   385   static size_t delta_capacity_until_GC(size_t word_size);

   387   // It is expected that this will be called when the current capacity

   388   // has been used and a GC should be considered.

   389   static bool should_expand(VirtualSpaceList* vsl, size_t word_size);

   391   // Calculate the new high-water mark at which to induce

   392   // a GC.

   393   static void compute_new_size();

   394 };

   396 #endif // SHARE_VM_MEMORY_METASPACE_HPP

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/memory/metaspace.hpp@740e263c80c6

src/share/vm/memory/metaspace.hpp