public void dumpLog(Logger logger) {
    hasDumped = true;
    int ix = 0;
    logger.info("Dumping LLAP IO trace; " + (offset << 3) + " bytes");
    while (ix < offset) {
      ix = dumpOneLine(ix, logger, log);
    }
  }
Single threaded IO trace.
Note: this can be made MTT merely by using an AtomicInteger, and storing a thread ID.
ql/src/java/org/apache/hadoop/hive/ql/io/orc/encoded/IoTrace.java