p2p: limit the outbound dialing too

This commit is contained in:
Péter Szilágyi 2015-04-30 15:06:05 +03:00
parent 97c37356fd
commit 3953bf0031

@ -27,6 +27,9 @@ const (
// 'added as peer'.
maxAcceptConns = 50
// Maximum number of concurrently dialing outbound connections.
maxDialingConns = 50
// total timeout for encryption handshake and protocol
// handshake in both directions.
handshakeTimeout = 5 * time.Second
@ -401,7 +404,11 @@ func (srv *Server) dialLoop() {
defer srv.loopWG.Done()
defer refresh.Stop()
// TODO: maybe limit number of active dials
// Limit the number of concurrent dials
slots := make(chan struct{}, maxDialingConns)
for i := 0; i < maxDialingConns; i++ {
slots <- struct{}{}
}
dial := func(dest *discover.Node) {
// Don't dial nodes that would fail the checks in addPeer.
// This is important because the connection handshake is a lot
@ -413,6 +420,9 @@ func (srv *Server) dialLoop() {
if !ok || dialing[dest.ID] {
return
}
// Request a dial slot to prevent CPU exhaustion
<-slots
defer func() { slots <- struct{}{} }()
dialing[dest.ID] = true
srv.peerWG.Add(1)