public synchronized void setPerfLogStarts(Phase phase, Map<String, Long> perfLogStarts) {
    perfLogStartMap.put(phase, perfLogStarts);
  }
@param phase phase of query
@param perfLogStarts map of PerfLogger call-trace name and start time in milliseconds, during given phase.
ql/src/java/org/apache/hadoop/hive/ql/QueryDisplay.java