added check to make sure there is at least 1 worker if there are jobs

modules/Bio/EnsEMBL/Hive/Queen.pm

@@ -203,6 +203,7 @@ sub update_analysis_stats {
     if($status eq 'READY') {
       $analysisStats->unclaimed_job_count($count);
       my $numWorkers = $count/$analysisStats->batch_size;
+      $numWorkers=1 if($numWorkers<1);
       if($analysisStats->hive_capacity>0 and $numWorkers > $analysisStats->hive_capacity) {
         $numWorkers=$analysisStats->hive_capacity;
       }