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
  21  * questions.
  22  *
  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     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

  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
  21  * questions.
  22  *
  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 private:
  35 
  36   void trace_gen_sizes(const char* const str) {
  37     if (TracePageSizes) {
  38       tty->print_cr("%s:  " SIZE_FORMAT "," SIZE_FORMAT " "
  39                     SIZE_FORMAT "," SIZE_FORMAT " "
  40                     SIZE_FORMAT,
  41                     str,
  42                     _min_gen1_size / K, _max_gen1_size / K,
  43                     _min_gen0_size / K, _max_gen0_size / K,
  44                     _max_heap_byte_size / K);
  45     }
  46   }
  47 
  48 public:
  49   GenerationSizer() {
  50     initialize_all();


  51   }
  52 
  53   void initialize_flags() {
  54     // Do basic sizing work
  55     TwoGenerationCollectorPolicy::initialize_flags();
  56 
  57     // If the user hasn't explicitly set the number of worker
  58     // threads, set the count.
  59     assert(UseSerialGC ||
  60            !FLAG_IS_DEFAULT(ParallelGCThreads) ||
  61            (ParallelGCThreads > 0),
  62            "ParallelGCThreads should be set before flag initialization");
  63 
  64     // The survivor ratio's are calculated "raw", unlike the
  65     // default gc, which adds 2 to the ratio value. We need to
  66     // make sure the values are valid before using them.
  67     if (MinSurvivorRatio < 3) {
  68       MinSurvivorRatio = 3;
  69     }
  70 
  71     if (InitialSurvivorRatio < 3) {
  72       InitialSurvivorRatio = 3;
  73     }
  74   }
  75 
  76   void initialize_size_info() {
  77     TwoGenerationCollectorPolicy::initialize_size_info();
  78 
  79     trace_gen_sizes("ps heap raw");
  80     const size_t page_sz = os::page_size_for_region(_min_heap_byte_size,
  81                                                     _max_heap_byte_size,
  82                                                     8);
  83 
  84     // Can a page size be something else than a power of two?
  85     assert(is_power_of_2((intptr_t)page_sz), "must be a power of 2");
  86     _min_alignment = round_to(page_sz, intra_heap_alignment());
  87 
  88     // Update sizes to reflect the selected page size.
  89     _min_gen0_size = align_size_up(_min_gen0_size, _min_alignment);
  90     _initial_gen0_size = MAX2(align_size_up_(_initial_gen0_size, _min_alignment), _min_gen0_size);
  91     _max_gen0_size = align_size_up(_max_gen0_size, _min_alignment);
  92 
  93     // Align old gen size down to preserve specified heap size. Adjust all other values.
  94     _max_gen1_size = max_heap_byte_size() - _max_gen0_size;
  95     _min_gen1_size = MIN2(align_size_up_(_min_gen1_size, _min_alignment), _max_gen1_size);
  96     _initial_gen1_size = MIN2(align_size_up_(_initial_gen1_size, _min_alignment), _max_gen1_size);
  97 
  98     trace_gen_sizes("ps heap rnd");
  99   }
 100 };
 101 
 102 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_GENERATIONSIZER_HPP