protected Set sendMessage(DistributionMessage m) {
    return sys.getDistributionManager().putOutgoing(m);
  }
Returns normally if succeeded to get data, otherwise throws an exception

@param th a test hook
@return true if parts of the query need to be retried, otherwise false
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionedRegionQueryEvaluator.java