code: function findOrCreateInstance(callback) {
      var models = self._meshApp.models;
      var Instance = models.ServiceInstance;
  
      service.instances(function(err, instances) {
        if (err) return callback(err);
        if (instances.length > 0) return callback();
  
        debug('onServiceUpdate: create first instance');
  
        var instance = new Instance({
          executorId: 1,
          serverServiceId: service.id,
          groupId: 1,
          cpus: 'STRONGLOOP_CLUSTER' in process.env ?
            process.env.STRONGLOOP_CLUSTER : 'CPU',
  
          // allow starting tracing on all instances via env for testing purposes
          tracingEnabled: !!process.env.STRONGLOOP_TRACING || false,
        });
        instance.save(callback);
      });
    }
docs: XXX(sam) I don't understand why we create an instance if one doesn't exist yet. We don't appear to need it, why not let it come into existence on deploy or start?