Method GcMemory

be/src/runtime/mem-tracker.cc:545–572

}

bool MemTracker::GcMemory(int64_t max_consumption) {
  if (max_consumption < 0) return true;
  lock_guard<mutex> l(gc_lock_);
  if (consumption_metric_ != NULL) RefreshConsumptionFromMetric();
  int64_t pre_gc_consumption = consumption();
  // Check if someone gc'd before us
  if (pre_gc_consumption < max_consumption) return false;
  if (num_gcs_metric_ != NULL) num_gcs_metric_->Increment(1);

  int64_t curr_consumption = pre_gc_consumption;
  // Try to free up some memory
  for (int i = 0; i < gc_functions_.size(); ++i) {
    // Try to free up the amount we are over plus some extra so that we don't have to
    // immediately GC again. Don't free all the memory since that can be unnecessarily
    // expensive.
    const int64_t EXTRA_BYTES_TO_FREE = 512L * 1024L * 1024L;
    int64_t bytes_to_free = curr_consumption - max_consumption + EXTRA_BYTES_TO_FREE;
    gc_functions_[i](bytes_to_free);
    if (consumption_metric_ != NULL) RefreshConsumptionFromMetric();
    curr_consumption = consumption();
    if (max_consumption - curr_consumption <= EXTRA_BYTES_TO_FREE) break;
  }

  if (bytes_freed_by_last_gc_metric_ != NULL) {
    bytes_freed_by_last_gc_metric_->SetValue(pre_gc_consumption - curr_consumption);
  }
  return curr_consumption > max_consumption;
}

Status ScopedMemTracker::TryConsume(int64_t size) {
  DCHECK(tracker_ != nullptr);