protected final int sleep(int sleepMultiplier) {
    if (sleepMultiplier < maxRetriesMultiplier) {
      sleepMultiplier++;
    }
    Threads.sleep(sleepForRetries * sleepMultiplier);
    return sleepMultiplier;
  }
Creates a reader worker for a given WAL queue. Reads WAL entries off a given queue, batches the
entries, and puts them on a batch queue.
@param fs            the files system to use
@param conf          configuration to use
@param logQueue      The WAL queue to read off of
@param startPosition position in the first WAL to start reading from
@param filter        The filter to use while reading
@param source        replication source
hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSourceWALReader.java