6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads
Summary: Use _max_num_q = max(discovery_degree, processing_degree), and let balance_queues() redistribute from discovery_degree to processing_degree of queues. This should also allow a more dynamic and flexible parallelism policy in the future.
Reviewed-by: jmasa, johnc
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#ifndef SHARE_VM_MEMORY_COMPACTPERMGEN_HPP
#define SHARE_VM_MEMORY_COMPACTPERMGEN_HPP
#include "memory/generation.hpp"
#include "memory/permGen.hpp"
class ContigPermSpace;
class CardTableModRefBS;
class CompactingPermGenGen;
class PermanentGenerationSpec;
// A PermGen implemented with a contiguous space.
class CompactingPermGen: public PermGen {
friend class VMStructs;
protected:
// The "generation" view.
OneContigSpaceCardGeneration* _gen;
public:
CompactingPermGen(ReservedSpace rs, ReservedSpace shared_rs,
size_t initial_byte_size, GenRemSet* remset,
PermanentGenerationSpec* perm_spec);
HeapWord* mem_allocate(size_t size);
void compute_new_size();
Generation* as_gen() const { return _gen; }
};
#endif // SHARE_VM_MEMORY_COMPACTPERMGEN_HPP