private void writeSortedEntries(Path dest, int part, final List<Pair<LogFileKey,LogFileValue>> kv) throws IOException {
String path = dest + String.format("/part-r-%05d", part);
log.debug("Writing partial log file to DSF " + path);
log.debug("Sorting");
Span span = Trace.start("Logger sort");
span.data("logfile", dest.getName());
Collections.sort(kv, new Comparator<Pair<LogFileKey,LogFileValue>>() {
@Override
public int compare(Pair<LogFileKey,LogFileValue> o1, Pair<LogFileKey,LogFileValue> o2) {
return o1.getFirst().compareTo(o2.getFirst());
}