long getNanoTimePassedSinceLastFlushedChunk(long nowNanoTime) {
      return myPrevFlushedChunkCreatedNanoTime > 0 ? nowNanoTime - myPrevFlushedChunkCreatedNanoTime
                                                   : nowNanoTime - myCreatedNanoTime;
    }
long getNanoTimePassedSinceLastFlushedChunk(long nowNanoTime)