Fix performance degradation introduced by GW code

This impacted even non gateway traffic

Signed-off-by: Ivan Kozlovic <ivan@synadia.com>

server/client.go

@@ -2133,22 +2133,21 @@ func (c *client) processInboundClientMsg(msg []byte) {
 		c.checkForImportServices(c.acc, msg)
 	}
 
-	var qa [16][]byte
-	queues := qa[:0]
+	var qnames [][]byte
 
 	// Check for no interest, short circuit if so.
 	// This is the fanout scale.
 	if len(r.psubs)+len(r.qsubs) > 0 {
-		var qnames *[][]byte
+		var collect bool
 		// If we have queue subs in this cluster, then if we run in gateway
 		// mode and the remote gateways have queue subs, then we need to
 		// collect the queue groups this message was sent to so that we
 		// exclude them when sending to gateways.
 		if len(r.qsubs) > 0 && c.srv.gateway.enabled &&
 			atomic.LoadInt64(&c.srv.gateway.totalQSubs) > 0 {
-			qnames = &queues
+			collect = true
 		}
-		c.processMsgResults(c.acc, r, msg, c.pa.subject, c.pa.reply, qnames)
+		qnames = c.processMsgResults(c.acc, r, msg, c.pa.subject, c.pa.reply, collect)
 	}
 
 	// Now deal with gateways
@@ -2161,7 +2160,7 @@ func (c *client) processInboundClientMsg(msg []byte) {
 		if len(r.psubs) == 1 && r.psubs[0].client.gw != nil {
 			c.sendReplyMsgDirectToGateway(c.acc, r.psubs[0], msg)
 		} else {
-			c.sendMsgToGateways(c.acc, msg, c.pa.subject, c.pa.reply, queues)
+			c.sendMsgToGateways(c.acc, msg, c.pa.subject, c.pa.reply, qnames)
 		}
 	}
 }
@@ -2195,7 +2194,7 @@ func (c *client) checkForImportServices(acc *Account, msg []byte) {
 		if c.kind == ROUTER || c.kind == GATEWAY && c.pa.queues == nil && len(rr.qsubs) > 0 {
 			c.makeQFilter(rr.qsubs)
 		}
-		c.processMsgResults(rm.acc, rr, msg, []byte(rm.to), nrr, nil)
+		c.processMsgResults(rm.acc, rr, msg, []byte(rm.to), nrr, false)
 		// If this is not a gateway connection but gateway is enabled,
 		// try to send this converted message to all gateways.
 		if c.kind != GATEWAY && c.srv.gateway.enabled {
@@ -2240,7 +2239,8 @@ func (c *client) addSubToRouteTargets(sub *subscription) {
 }
 
 // This processes the sublist results for a given message.
-func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject, reply []byte, queues *[][]byte) {
+func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject, reply []byte, collect bool) [][]byte {
+	var queues [][]byte
 	// msg header for clients.
 	msgh := c.msgb[1:msgHeadProtoLen]
 	msgh = append(msgh, subject...)
@@ -2283,7 +2283,7 @@ func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject,
 
 	// If we are sourced from a route we need to have direct filtered queues.
 	if c.kind == ROUTER && c.pa.queues == nil {
-		return
+		return queues
 	}
 
 	// Set these up to optionally filter based on the queue lists.
@@ -2346,8 +2346,8 @@ func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject,
 					continue
 				} else {
 					c.addSubToRouteTargets(sub)
-					if queues != nil {
-						*queues = append(*queues, sub.queue)
+					if collect {
+						queues = append(queues, sub.queue)
 					}
 				}
 				break
@@ -2366,8 +2366,8 @@ func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject,
 			if c.deliverMsg(sub, mh, msg) {
 				// Clear rsub
 				rsub = nil
-				if queues != nil {
-					*queues = append(*queues, sub.queue)
+				if collect {
+					queues = append(queues, sub.queue)
 				}
 				break
 			}
@@ -2377,8 +2377,8 @@ func (c *client) processMsgResults(acc *Account, r *SublistResult, msg, subject,
 			// If we are here we tried to deliver to a local qsub
 			// but failed. So we will send it to a remote.
 			c.addSubToRouteTargets(rsub)
-			if queues != nil {
-				*queues = append(*queues, rsub.queue)
+			if collect {
+				queues = append(queues, rsub.queue)
 			}
 		}
 	}
@@ -2387,7 +2387,7 @@ sendToRoutes:
 
 	// If no messages for routes return here.
 	if len(c.in.rts) == 0 {
-		return
+		return queues
 	}
 
 	// We address by index to avoid struct copy.
@@ -2418,6 +2418,7 @@ sendToRoutes:
 		mh = append(mh, _CRLF_...)
 		c.deliverMsg(rt.sub, mh, msg)
 	}
+	return queues
 }
 
 func (c *client) pubPermissionViolation(subject []byte) {

server/const.go

@@ -40,7 +40,7 @@ var (
 
 const (
 	// VERSION is the current version for the server.
-	VERSION = "2.0.0-beta.6"
+	VERSION = "2.0.0-beta.7"
 
 	// PROTO is the currently supported protocol.
 	// 0 was the original

server/gateway.go

@@ -2174,7 +2174,7 @@ func (c *client) processInboundGatewayMsg(msg []byte) {
 		}
 	}
 
-	c.processMsgResults(acc, r, msg, c.pa.subject, c.pa.reply, nil)
+	c.processMsgResults(acc, r, msg, c.pa.subject, c.pa.reply, false)
 }
 
 // Indicates that the remote which we are sending messages to

server/route.go

@@ -308,7 +308,7 @@ func (c *client) processInboundRoutedMsg(msg []byte) {
 		}
 	}
 
-	c.processMsgResults(acc, r, msg, c.pa.subject, c.pa.reply, nil)
+	c.processMsgResults(acc, r, msg, c.pa.subject, c.pa.reply, false)
 }
 
 // Helper function for routes and gateways to create qfilters need for