jdk8-mips64-public/hotspot: src/share/vm/memory/metaspace.hpp@59a58e20dc60

     1 /*

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

     4  *

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

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     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).

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

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    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, NonClassType};

    90   enum MetaspaceType {

    91     StandardMetaspaceType,

    92     BootMetaspaceType,

    93     ROMetaspaceType,

    94     ReadWriteMetaspaceType,

    95     AnonymousMetaspaceType,

    96     ReflectionMetaspaceType

    97   };

    99  private:

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

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

   103   static size_t align_word_size_up(size_t);

   105   static size_t _first_chunk_word_size;

   106   static size_t _first_class_chunk_word_size;

   108   SpaceManager* _vsm;

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

   111   SpaceManager* _class_vsm;

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

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

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

   117   static VirtualSpaceList* _space_list;

   118   static VirtualSpaceList* _class_space_list;

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

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

   123  public:

   125   Metaspace(Mutex* lock, MetaspaceType type);

   126   ~Metaspace();

   128   // Initialize globals for Metaspace

   129   static void global_initialize();

   130   static void initialize_class_space(ReservedSpace rs);

   132   static size_t first_chunk_word_size() { return _first_chunk_word_size; }

   133   static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }

   135   char*  bottom() const;

   136   size_t used_words(MetadataType mdtype) const;

   137   size_t free_words(MetadataType mdtype) const;

   138   size_t capacity_words(MetadataType mdtype) const;

   139   size_t waste_words(MetadataType mdtype) const;

   141   static Metablock* allocate(ClassLoaderData* loader_data, size_t size,

   142                             bool read_only, MetadataType mdtype, TRAPS);

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

   145   MetaWord* expand_and_allocate(size_t size,

   146                                 MetadataType mdtype);

   148   static bool is_initialized() { return _class_space_list != NULL; }

   150   static bool contains(const void *ptr);

   151   void dump(outputStream* const out) const;

   153   void print_on(outputStream* st) const;

   154   // Debugging support

   155   void verify();

   156 };

   158 class MetaspaceAux : AllStatic {

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

   161   static size_t used_in_bytes(Metaspace::MetadataType mdtype);

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

   163   static size_t capacity_in_bytes(Metaspace::MetadataType mdtype);

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

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

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

   169  public:

   170   // Total of space allocated to metadata in all Metaspaces

   171   static size_t used_in_bytes() {

   172     return used_in_bytes(Metaspace::ClassType) +

   173            used_in_bytes(Metaspace::NonClassType);

   174   }

   176   // Total of available space in all Metaspaces

   177   // Total of capacity allocated to all Metaspaces.  This includes

   178   // space in Metachunks not yet allocated and in the Metachunk

   179   // freelist.

   180   static size_t capacity_in_bytes() {

   181     return capacity_in_bytes(Metaspace::ClassType) +

   182            capacity_in_bytes(Metaspace::NonClassType);

   183   }

   185   // Total space reserved in all Metaspaces

   186   static size_t reserved_in_bytes() {

   187     return reserved_in_bytes(Metaspace::ClassType) +

   188            reserved_in_bytes(Metaspace::NonClassType);

   189   }

   191   static size_t min_chunk_size();

   193   // Print change in used metadata.

   194   static void print_metaspace_change(size_t prev_metadata_used);

   195   static void print_on(outputStream * out);

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

   198   static void print_waste(outputStream* out);

   199   static void dump(outputStream* out);

   200   static void verify_free_chunks();

   201 };

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

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

   205 // Metaspaces.

   207 class MetaspaceGC : AllStatic {

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

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

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

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

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

   214   static size_t _capacity_until_GC;

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

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

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

   219   static bool _expand_after_GC;

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

   222   // be started.

   223   static bool _should_concurrent_collect;

   225   static uint _shrink_factor;

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

   229   static size_t shrink_factor() { return _shrink_factor; }

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

   232  public:

   234   static size_t capacity_until_GC() { return _capacity_until_GC; }

   235   static size_t capacity_until_GC_in_bytes() { return _capacity_until_GC * BytesPerWord; }

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

   237   static void dec_capacity_until_GC(size_t v) {

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

   239   }

   240   static bool expand_after_GC()           { return _expand_after_GC; }

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

   243   static bool should_concurrent_collect() { return _should_concurrent_collect; }

   244   static void set_should_concurrent_collect(bool v) {

   245     _should_concurrent_collect = v;

   246   }

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

   249   static size_t delta_capacity_until_GC(size_t word_size);

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

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

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

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

   256   // a GC.

   257   static void compute_new_size();

   258 };

   260 #endif // SHARE_VM_MEMORY_METASPACE_HPP

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

src/share/vm/memory/metaspace.hpp@59a58e20dc60

src/share/vm/memory/metaspace.hpp