private void doLookups(Map<String,Map<KeyExtent,List<Range>>> binnedRanges, final ResultReceiver receiver, List<Column> columns) {
if (timedoutServers.containsAll(binnedRanges.keySet())) {
// all servers have timed out
throw new TimedOutException(timedoutServers);
}
// when there are lots of threads and a few tablet servers
// it is good to break request to tablet servers up, the
// following code determines if this is the case