CCQ: Query server response channel too small (#3502)

node/cmd/ccq/p2p.go

@@ -175,7 +175,12 @@ func runP2P(ctx context.Context, priv crypto.PrivKey, port uint, networkID, boot
 							Signatures: responses[requestSignature][digest],
 						}
 						delete(responses, requestSignature)
-						pendingResponse.ch <- s
+						select {
+						case pendingResponse.ch <- s:
+							logger.Debug("forwarded query response")
+						default:
+							logger.Error("failed to write query response to channel, dropping it")
+						}
 					}
 				} else {
 					logger.Warn("received observation by unknown guardian - is our guardian set outdated?",

node/cmd/ccq/pending_request.go

@@ -26,7 +26,8 @@ type PendingResponses struct {
 
 func NewPendingResponses() *PendingResponses {
 	return &PendingResponses{
-		pendingResponses: make(map[string]*PendingResponse),
+		// Make this channel bigger than the number of responses we ever expect to get for a query.
+		pendingResponses: make(map[string]*PendingResponse, 100),
 	}
 }