src/hotspot/share/gc/g1/g1HeapTransition.cpp

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 * version 2 for more details (a copy is included in the LICENSE file that
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#include "precompiled.hpp"
#include "gc/g1/g1CollectedHeap.hpp"
#include "gc/g1/g1HeapTransition.hpp"
#include "gc/g1/g1Policy.hpp"
#include "logging/logStream.hpp"
#include "memory/metaspaceUtils.hpp"

G1HeapTransition::Data::Data(G1CollectedHeap* g1_heap) :
  _eden_length(g1_heap->eden_regions_count()),
  _survivor_length(g1_heap->survivor_regions_count()),
  _old_length(g1_heap->old_regions_count()),
  _humongous_length(g1_heap->humongous_regions_count()),
  _meta_sizes(MetaspaceUtils::get_combined_statistics()),
  _eden_length_per_node(nullptr),
  _survivor_length_per_node(nullptr) {

  uint node_count = G1NUMA::numa()->num_active_nodes();

  if (node_count > 1) {
    LogTarget(Debug, gc, heap, numa) lt;

    if (lt.is_enabled()) {
      _eden_length_per_node = NEW_C_HEAP_ARRAY(uint, node_count, mtGC);
      _survivor_length_per_node = NEW_C_HEAP_ARRAY(uint, node_count, mtGC);

      for (uint i = 0; i < node_count; i++) {
        _eden_length_per_node[i] = g1_heap->eden_regions_count(i);
        _survivor_length_per_node[i] = g1_heap->survivor_regions_count(i);
      }
    }
  }
}

G1HeapTransition::Data::~Data() {
  FREE_C_HEAP_ARRAY(uint, _eden_length_per_node);
  FREE_C_HEAP_ARRAY(uint, _survivor_length_per_node);
}

G1HeapTransition::G1HeapTransition(G1CollectedHeap* g1_heap) : _g1_heap(g1_heap), _before(g1_heap) { }

struct DetailedUsage : public StackObj {
  size_t _eden_used;
  size_t _survivor_used;
  size_t _old_used;
  size_t _humongous_used;

  size_t _eden_region_count;
  size_t _survivor_region_count;
  size_t _old_region_count;
  size_t _humongous_region_count;

  DetailedUsage() :
    _eden_used(0), _survivor_used(0), _old_used(0), _humongous_used(0),
    _eden_region_count(0), _survivor_region_count(0), _old_region_count(0),
    _humongous_region_count(0) {}
};

class DetailedUsageClosure: public HeapRegionClosure {
public:
  DetailedUsage _usage;
  bool do_heap_region(HeapRegion* r) {
    if (r->is_old()) {
      _usage._old_used += r->used();
      _usage._old_region_count++;
    } else if (r->is_survivor()) {
      _usage._survivor_used += r->used();
      _usage._survivor_region_count++;
    } else if (r->is_eden()) {
      _usage._eden_used += r->used();
      _usage._eden_region_count++;
    } else if (r->is_humongous()) {
      _usage._humongous_used += r->used();
      _usage._humongous_region_count++;
    } else {
      assert(r->used() == 0, "Expected used to be 0 but it was " SIZE_FORMAT, r->used());
    }
    return false;
  }
};

static void log_regions(const char* msg, size_t before_length, size_t after_length, size_t capacity,
                        uint* before_per_node_length, uint* after_per_node_length) {
  LogTarget(Info, gc, heap) lt;

  if (lt.is_enabled()) {
    LogStream ls(lt);

    ls.print("%s regions: " SIZE_FORMAT "->" SIZE_FORMAT "("  SIZE_FORMAT ")",
             msg, before_length, after_length, capacity);
    // Not null only if gc+heap+numa at Debug level is enabled.
    if (before_per_node_length != nullptr && after_per_node_length != nullptr) {
      G1NUMA* numa = G1NUMA::numa();
      uint num_nodes = numa->num_active_nodes();
      const int* node_ids = numa->node_ids();
      ls.print(" (");
      for (uint i = 0; i < num_nodes; i++) {
        ls.print("%d: %u->%u", node_ids[i], before_per_node_length[i], after_per_node_length[i]);
        // Skip adding below if it is the last one.
        if (i != num_nodes - 1) {
          ls.print(", ");
        }
      }
      ls.print(")");
    }
    ls.print_cr("");
  }
}

void G1HeapTransition::print() {
  Data after(_g1_heap);

  size_t eden_capacity_length_after_gc = _g1_heap->policy()->young_list_target_length() - after._survivor_length;
  size_t survivor_capacity_length_before_gc = _g1_heap->policy()->max_survivor_regions();

  DetailedUsage usage;
  if (log_is_enabled(Trace, gc, heap)) {
    DetailedUsageClosure blk;
    _g1_heap->heap_region_iterate(&blk);
    usage = blk._usage;
    assert(usage._eden_region_count == 0, "Expected no eden regions, but got " SIZE_FORMAT, usage._eden_region_count);
    assert(usage._survivor_region_count == after._survivor_length, "Expected survivors to be " SIZE_FORMAT " but was " SIZE_FORMAT,
        after._survivor_length, usage._survivor_region_count);
    assert(usage._old_region_count == after._old_length, "Expected old to be " SIZE_FORMAT " but was " SIZE_FORMAT,
        after._old_length, usage._old_region_count);
    assert(usage._humongous_region_count == after._humongous_length, "Expected humongous to be " SIZE_FORMAT " but was " SIZE_FORMAT,
        after._humongous_length, usage._humongous_region_count);
  }

  log_regions("Eden", _before._eden_length, after._eden_length, eden_capacity_length_after_gc,
              _before._eden_length_per_node, after._eden_length_per_node);
  log_trace(gc, heap)(" Used: 0K, Waste: 0K");

  log_regions("Survivor", _before._survivor_length, after._survivor_length, survivor_capacity_length_before_gc,
              _before._survivor_length_per_node, after._survivor_length_per_node);
  log_trace(gc, heap)(" Used: " SIZE_FORMAT "K, Waste: " SIZE_FORMAT "K",
      usage._survivor_used / K, ((after._survivor_length * HeapRegion::GrainBytes) - usage._survivor_used) / K);

  log_info(gc, heap)("Old regions: " SIZE_FORMAT "->" SIZE_FORMAT,
                     _before._old_length, after._old_length);
  log_trace(gc, heap)(" Used: " SIZE_FORMAT "K, Waste: " SIZE_FORMAT "K",
      usage._old_used / K, ((after._old_length * HeapRegion::GrainBytes) - usage._old_used) / K);

  log_info(gc, heap)("Humongous regions: " SIZE_FORMAT "->" SIZE_FORMAT,
                     _before._humongous_length, after._humongous_length);
  log_trace(gc, heap)(" Used: " SIZE_FORMAT "K, Waste: " SIZE_FORMAT "K",
      usage._humongous_used / K, ((after._humongous_length * HeapRegion::GrainBytes) - usage._humongous_used) / K);

  MetaspaceUtils::print_metaspace_change(_before._meta_sizes);
}