@Override
  public String toString() {
    long state = this.state.get();
    int flags = State.getAllFlags(state);
    return "0x" + Integer.toHexString(System.identityHashCode(this)) + "("
        + State.getRefCount(state) + (flags == 0 ? "" : (", "
            + State.toFlagString(flags))) + ")";
  }
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