From 21a4f8c0c82a0b980a8cb5fdf6460148cdcdb565 Mon Sep 17 00:00:00 2001
From: Yusef Napora <yusef@protocol.ai>
Date: Wed, 6 May 2020 10:25:14 -0400
Subject: [PATCH] only call fragmentRPC if we're over the size limit

---
 gossipsub.go | 35 ++++++++++++++++++++++-------------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/gossipsub.go b/gossipsub.go
index 2e90b61..cf6537d 100644
--- a/gossipsub.go
+++ b/gossipsub.go
@@ -899,16 +899,31 @@ func (gs *GossipSubRouter) sendRPC(p peer.ID, out *RPC) {
 		return
 	}
 
-	// fragment into multiple RPCs if necessary
-	outRPCs, err := fragmentRPC(out, gs.p.maxMessageSize)
-	if err != nil {
-		log.Warnf("unable to fragment message to peer %s: %s", p, err)
-		gs.tracer.DropRPC(out, p)
+	dropRPC := func(rpc *RPC, template string, args ...interface{}) {
+		log.Warnf(template, args...)
+		gs.tracer.DropRPC(rpc, p)
 		// push control messages that need to be retried
-		ctl := out.GetControl()
+		ctl := rpc.GetControl()
 		if ctl != nil {
 			gs.pushControl(p, ctl)
 		}
+	}
+
+	// If we're below the max message size, go ahead and send
+	if out.Size() < gs.p.maxMessageSize {
+		select {
+		case mch <- out:
+			gs.tracer.SendRPC(out, p)
+		default:
+			dropRPC(out, "dropping message to peer %s: queue full", p)
+		}
+		return
+	}
+
+	// If we're too big, fragment into multiple RPCs and send each sequentially
+	outRPCs, err := fragmentRPC(out, gs.p.maxMessageSize)
+	if err != nil {
+		dropRPC(out, "unable to fragment message to peer %s: %s", p, err)
 		return
 	}
 
@@ -917,13 +932,7 @@ func (gs *GossipSubRouter) sendRPC(p peer.ID, out *RPC) {
 		case mch <- rpc:
 			gs.tracer.SendRPC(rpc, p)
 		default:
-			log.Infof("dropping message to peer %s: queue full", p)
-			gs.tracer.DropRPC(rpc, p)
-			// push control messages that need to be retried
-			ctl := rpc.GetControl()
-			if ctl != nil {
-				gs.pushControl(p, ctl)
-			}
+			dropRPC(rpc, "dropping message to peer %s: queue full", p)
 		}
 	}
 }