// Returns nil connection and nil error if no connection could be established for valid reasons.
func (cl *Client) dialAndCompleteHandshake(opts outgoingConnOpts) (c *PeerConn, err error) {
- err = cl.config.DialRateLimiter.Wait(context.Background())
- if err != nil {
- return
+ // It would be better if dial rate limiting could be tested when considering to open connections
+ // instead. Doing it here means if the limit is low, and the half-open limit is high, we could
+ // end up with lots of outgoing connection attempts pending that were initiated on stale data.
+ {
+ dialReservation := cl.config.DialRateLimiter.Reserve()
+ if !opts.receivedHolepunchConnect {
+ if !dialReservation.OK() {
+ err = errors.New("can't make dial limit reservation")
+ return
+ }
+ time.Sleep(dialReservation.Delay())
+ }
}
torrent.Add("establish outgoing connection", 1)
addr := opts.peerInfo.Addr