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24
25#ifndef SHARE_GC_G1_HEAPREGIONBOUNDS_HPP
26#define SHARE_GC_G1_HEAPREGIONBOUNDS_HPP
27
28#include "memory/allocation.hpp"
29
30class HeapRegionBounds : public AllStatic {
31private:
32 // Minimum region size; we won't go lower than that.
33 // We might want to decrease this in the future, to deal with small
34 // heaps a bit more efficiently.
35 static const size_t MIN_REGION_SIZE = 1024 * 1024;
36
37 // Maximum region size; we don't go higher than that. There's a good
38 // reason for having an upper bound. We don't want regions to get too
39 // large, otherwise cleanup's effectiveness would decrease as there
40 // will be fewer opportunities to find totally empty regions after
41 // marking.
42 static const size_t MAX_REGION_SIZE = 32 * 1024 * 1024;
43
44 // The automatic region size calculation will try to have around this
45 // many regions in the heap (based on the min heap size).
46 static const size_t TARGET_REGION_NUMBER = 2048;
47
48public:
49 static inline size_t min_size();
50 static inline size_t max_size();
51 static inline size_t target_number();
52};
53
54#endif // SHARE_GC_G1_HEAPREGIONBOUNDS_HPP
55