8227084: Add timing information for merge heap root preparation
Reviewed-by: sangheki, kbarrett
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#ifndef SHARE_GC_G1_HEAPREGIONBOUNDS_HPP
#define SHARE_GC_G1_HEAPREGIONBOUNDS_HPP
#include "memory/allocation.hpp"
class HeapRegionBounds : public AllStatic {
private:
// Minimum region size; we won't go lower than that.
// We might want to decrease this in the future, to deal with small
// heaps a bit more efficiently.
static const size_t MIN_REGION_SIZE = 1024 * 1024;
// Maximum region size; we don't go higher than that. There's a good
// reason for having an upper bound. We don't want regions to get too
// large, otherwise cleanup's effectiveness would decrease as there
// will be fewer opportunities to find totally empty regions after
// marking.
static const size_t MAX_REGION_SIZE = 32 * 1024 * 1024;
// The automatic region size calculation will try to have around this
// many regions in the heap (based on the min heap size).
static const size_t TARGET_REGION_NUMBER = 2048;
public:
static inline size_t min_size();
static inline size_t max_size();
static inline size_t target_number();
};
#endif // SHARE_GC_G1_HEAPREGIONBOUNDS_HPP