code: func (r *SearchRequest) MaxConcurrentShardRequests(size int) *SearchRequest {
  	r.maxConcurrentShardRequests = &size
  	return r
  }
docs: // MaxConcurrentShardRequests sets the number of shard requests that should
  // be executed concurrently. This value should be used as a protection
  // mechanism to reduce the number of shard requests fired per high level
  // search request. Searches that hit the entire cluster can be throttled
  // with this number to reduce the cluster load. The default grows with
  // the number of nodes in the cluster but is at most 256.