jdk8-mips64-public/hotspot: src/share/vm/memory/permGen.hpp@e41cd7fd68a6

6794422: Perm gen expansion policy for concurrent collectors
Summary: Concurrent collectors should expand the perm gen without a full STW GC, but possibly by triggering a concurrent collection. Temporary band-aid for G1 where no concurrent collection is kicked off since the perm gen is not collected concurrently.
Reviewed-by: johnc

     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

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    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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    25 // All heaps contains a "permanent generation," containing permanent

    26 // (reflective) objects.  This is like a regular generation in some ways,

    27 // but unlike one in others, and so is split apart.

    29 class Generation;

    30 class GenRemSet;

    31 class CSpaceCounters;

    33 // PermGen models the part of the heap used to allocate class meta-data.

    35 class PermGen : public CHeapObj {

    36   friend class VMStructs;

    37  protected:

    38   size_t _capacity_expansion_limit;  // maximum expansion allowed without a

    39                                      // full gc occurring

    40   void set_capacity_expansion_limit(size_t limit) {

    41     assert_locked_or_safepoint(Heap_lock);

    42     _capacity_expansion_limit = limit;

    43   }

    45   HeapWord* mem_allocate_in_gen(size_t size, Generation* gen);

    46   // Along with mem_allocate_in_gen() above, implements policy for

    47   // "scheduling" allocation/expansion/collection of the perm gen.

    48   // The virtual method request_...() below can be overridden by

    49   // subtypes that want to implement a different expansion/collection

    50   // policy from the default provided.

    51   virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size,

    52                                                 GCCause::Cause prev_cause);

    54  public:

    55   enum Name {

    56     MarkSweepCompact, MarkSweep, ConcurrentMarkSweep

    57   };

    59   // Permanent allocation (initialized)

    60   virtual HeapWord* mem_allocate(size_t size) = 0;

    62   // Mark sweep support

    63   virtual void compute_new_size() = 0;

    65   // Ideally, we would use MI (IMHO) but we'll do delegation instead.

    66   virtual Generation* as_gen() const = 0;

    68   virtual void oop_iterate(OopClosure* cl) {

    69     Generation* g = as_gen();

    70     assert(g != NULL, "as_gen() NULL");

    71     g->oop_iterate(cl);

    72   }

    74   virtual void object_iterate(ObjectClosure* cl) {

    75     Generation* g = as_gen();

    76     assert(g != NULL, "as_gen() NULL");

    77     g->object_iterate(cl);

    78   }

    80   // Performance Counter support

    81   virtual void update_counters() {

    82     Generation* g = as_gen();

    83     assert(g != NULL, "as_gen() NULL");

    84     g->update_counters();

    85   }

    86 };

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

src/share/vm/memory/permGen.hpp@e41cd7fd68a6

src/share/vm/memory/permGen.hpp