jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.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 /*

     2  * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.

     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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    22  *

    23  */

    25 class CardTableRS;   // fwd decl

    26 class ConcurrentMarkSweepGeneration;

    28 // A PermGen implemented with a CMS space, collected by a CMS collector.

    29 class CMSPermGen:  public PermGen {

    30   friend class VMStructs;

    32  protected:

    33   // The "generation" view.

    34   ConcurrentMarkSweepGeneration* _gen;

    36   // Override default implementation from PermGen

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

    38                                                 GCCause::Cause prev_cause);

    40  public:

    41   CMSPermGen(ReservedSpace rs, size_t initial_byte_size,

    42              CardTableRS* ct, FreeBlockDictionary::DictionaryChoice);

    44   HeapWord* mem_allocate(size_t size);

    46   void compute_new_size();

    48   Generation* as_gen() const { return _gen; }

    49 };

    51 // This is the "generation" view of a CMSPermGen.

    52 class CMSPermGenGen: public ConcurrentMarkSweepGeneration {

    53   // Abstractly, this is a subtype that gets access to protected fields.

    54   friend class CMSPermGen;

    55 public:

    56   CMSPermGenGen(ReservedSpace rs, size_t initial_byte_size,

    57                        int level, CardTableRS* ct):

    58     // See comments in the constructor for CompactibleFreeListSpace

    59     // regarding not using adaptive free lists for a perm gen.

    60     ConcurrentMarkSweepGeneration(rs, initial_byte_size, // MinPermHeapExapnsion

    61       level, ct, false /* use adaptive freelists */,

    62       (FreeBlockDictionary::DictionaryChoice)CMSDictionaryChoice)

    63   {}

    65   void initialize_performance_counters();

    67   const char* name() const {

    68     return "concurrent-mark-sweep perm gen";

    69   }

    71   const char* short_name() const {

    72     return "CMS Perm";

    73   }

    75   bool must_be_youngest() const { return false; }

    76   bool must_be_oldest() const { return false; }

    77 };

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

src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp@e41cd7fd68a6

src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp