1 /*
   2  * Copyright (c) 2001, 2013, 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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  23  */
  24 
  25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_GENERATIONSIZER_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_GENERATIONSIZER_HPP
  27 
  28 #include "memory/collectorPolicy.hpp"
  29 
  30 // There is a nice batch of tested generation sizing code in
  31 // TwoGenerationCollectorPolicy. Lets reuse it!
  32 
  33 class GenerationSizer : public TwoGenerationCollectorPolicy {
  34  public:
  35   GenerationSizer() {
  36     // Partial init only!
  37     initialize_flags();
  38     initialize_size_info();
  39   }
  40 
  41   void initialize_flags() {
  42     // Do basic sizing work
  43     this->TwoGenerationCollectorPolicy::initialize_flags();
  44 
  45     // If the user hasn't explicitly set the number of worker
  46     // threads, set the count.
  47     assert(UseSerialGC ||
  48            !FLAG_IS_DEFAULT(ParallelGCThreads) ||
  49            (ParallelGCThreads > 0),
  50            "ParallelGCThreads should be set before flag initialization");
  51 
  52     // The survivor ratio's are calculated "raw", unlike the
  53     // default gc, which adds 2 to the ratio value. We need to
  54     // make sure the values are valid before using them.
  55     if (MinSurvivorRatio < 3) {
  56       MinSurvivorRatio = 3;
  57     }
  58 
  59     if (InitialSurvivorRatio < 3) {
  60       InitialSurvivorRatio = 3;
  61     }
  62   }
  63 
  64   size_t min_young_gen_size() { return _min_gen0_size; }
  65   size_t young_gen_size()     { return _initial_gen0_size; }
  66   size_t max_young_gen_size() { return _max_gen0_size; }
  67 
  68   size_t min_old_gen_size()   { return _min_gen1_size; }
  69   size_t old_gen_size()       { return _initial_gen1_size; }
  70   size_t max_old_gen_size()   { return _max_gen1_size; }
  71 };
  72 
  73 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_GENERATIONSIZER_HPP