src/hotspot/share/gc/parallel/psMemoryPool.cpp

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#include "gc/parallel/psMemoryPool.hpp"

PSGenerationPool::PSGenerationPool(PSOldGen* old_gen,
                                   const char* name,
                                   bool support_usage_threshold) :
  CollectedMemoryPool(name, old_gen->capacity_in_bytes(),
                      old_gen->reserved().byte_size(), support_usage_threshold), _old_gen(old_gen) {
}

MemoryUsage PSGenerationPool::get_memory_usage() {
  size_t maxSize   = (available_for_allocation() ? max_size() : 0);
  size_t used      = used_in_bytes();
  size_t committed = _old_gen->capacity_in_bytes();

  return MemoryUsage(initial_size(), used, committed, maxSize);
}

// The max size of EdenMutableSpacePool =
//     max size of the PSYoungGen - capacity of two survivor spaces
//
// Max size of PS eden space is changing due to ergonomic.
// PSYoungGen, PSOldGen, Eden, Survivor spaces are all resizable.
//
EdenMutableSpacePool::EdenMutableSpacePool(PSYoungGen* young_gen,
                                           MutableSpace* space,
                                           const char* name,
                                           bool support_usage_threshold) :
  CollectedMemoryPool(name, space->capacity_in_bytes(),
                      (young_gen->max_gen_size() -
                       young_gen->from_space()->capacity_in_bytes() -
                       young_gen->to_space()->capacity_in_bytes()),
                      support_usage_threshold),
  _young_gen(young_gen),
  _space(space) {
}

MemoryUsage EdenMutableSpacePool::get_memory_usage() {
  size_t maxSize   = (available_for_allocation() ? max_size() : 0);
  size_t used = used_in_bytes();
  size_t committed = _space->capacity_in_bytes();

  return MemoryUsage(initial_size(), used, committed, maxSize);
}

// The max size of SurvivorMutableSpacePool =
//     current capacity of the from-space
//
// PS from and to survivor spaces could have different sizes.
//
SurvivorMutableSpacePool::SurvivorMutableSpacePool(PSYoungGen* young_gen,
                                                   const char* name,
                                                   bool support_usage_threshold) :
  CollectedMemoryPool(name, young_gen->from_space()->capacity_in_bytes(),
                      young_gen->from_space()->capacity_in_bytes(),
                      support_usage_threshold), _young_gen(young_gen) {
}

MemoryUsage SurvivorMutableSpacePool::get_memory_usage() {
  size_t maxSize = (available_for_allocation() ? max_size() : 0);
  size_t used    = used_in_bytes();
  size_t committed = committed_in_bytes();
  return MemoryUsage(initial_size(), used, committed, maxSize);
}