src/hotspot/share/gc/g1/g1HeterogeneousHeapYoungGenSizer.hpp

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#ifndef SHARE_GC_G1_G1HETEROGENEOUSHEAPYOUNGGENSIZER_HPP
#define SHARE_GC_G1_G1HETEROGENEOUSHEAPYOUNGGENSIZER_HPP

#include "gc/g1/g1YoungGenSizer.hpp"

// This class prevents the size of young generation of G1 heap to exceed dram
// memory available. If set on command line, MaxRAM and MaxRAMFraction/MaxRAMPercentage
// are used to determine the maximum size that young generation can grow.
// Else we set the maximum size to 80% of dram available in the system.

class G1HeterogeneousHeapYoungGenSizer : public G1YoungGenSizer {
private:
  // maximum no of regions that young generation can grow to. Calculated in constructor.
  uint _max_young_length;
  void adjust_lengths_based_on_dram_memory();

public:
  G1HeterogeneousHeapYoungGenSizer();

  // Calculate the maximum length of the young gen given the number of regions
  // depending on the sizing algorithm.
  virtual void adjust_max_new_size(uint number_of_heap_regions);

  virtual void heap_size_changed(uint new_number_of_heap_regions);
};

#endif // SHARE_GC_G1_G1HETEROGENEOUSHEAPYOUNGGENSIZER_HPP