@Override
  public void removeProactiveEvictionMark() {
    long oldValue, newValue;
    do {
      oldValue = state.get();
      if (!State.hasFlags(oldValue, State.FLAG_MARKED)) {
        return;
      }
      newValue = State.switchFlag(oldValue, State.FLAG_MARKED);
    } while (!state.compareAndSet(oldValue, newValue));
  }
Marks this buffer as eligible for proactive eviction. No need to check refCount here.
@return buffer size
llap-server/src/java/org/apache/hadoop/hive/llap/cache/LlapAllocatorBuffer.java