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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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#include "gc/g1/g1MonitoringSupport.hpp"

#include "services/memoryPool.hpp"

#include "services/memoryUsage.hpp"

// This file contains the three classes that represent the memory

// pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and

// G1OldGenPool. In G1, unlike our other GCs, we do not have a

// physical space for each of those spaces. Instead, we allocate

// regions for all three spaces out of a single pool of regions (that

// pool basically covers the entire heap). As a result, the eden,

// survivor, and old gen are considered logical spaces in G1, as each

// is a set of non-contiguous regions. This is also reflected in the

// way we map them to memory pools here. The easiest way to have done

// this would have been to map the entire G1 heap to a single memory

// pool. However, it's helpful to show how large the eden and survivor

// get, as this does affect the performance and behavior of G1. Which

// is why we introduce the three memory pools implemented here.

//

// See comments in g1MonitoringSupport.hpp for additional details

// on this model.

//

class G1CollectedHeap;

// This class is shared by the three G1 memory pool classes

// (G1EdenPool, G1SurvivorPool, G1OldGenPool).

class G1MemoryPoolSuper : public CollectedMemoryPool {

protected:

  G1MonitoringSupport* _g1mm;

  // Would only be called from subclasses.

  G1MemoryPoolSuper(G1CollectedHeap* g1h,

                    const char* name,

                    size_t init_size,

                    size_t max_size,

                    bool support_usage_threshold);

};

// Memory pool that represents the G1 eden.

class G1EdenPool : public G1MemoryPoolSuper {

public:

  G1EdenPool(G1CollectedHeap* g1h, size_t initial_size);

  size_t used_in_bytes() { return _g1mm->eden_space_used(); }

  MemoryUsage get_memory_usage();

};

// Memory pool that represents the G1 survivor.

class G1SurvivorPool : public G1MemoryPoolSuper {

public:

  G1SurvivorPool(G1CollectedHeap* g1h, size_t initial_size);

  size_t used_in_bytes() { return _g1mm->survivor_space_used(); }

  MemoryUsage get_memory_usage();

};

// Memory pool that represents the G1 old gen.

class G1OldGenPool : public G1MemoryPoolSuper {

public:

  G1OldGenPool(G1CollectedHeap* g1h, size_t initial_size, size_t max_size);

  size_t used_in_bytes() { return _g1mm->old_gen_used(); }

  MemoryUsage get_memory_usage();

};