Make multicast gathering a bit smarter.

1 files changed, 24 insertions, 22 deletions

diff --git a/node/Multicaster.cpp b/node/Multicaster.cpp
index a3e600d9..8e3e3e29 100644
--- a/node/Multicaster.cpp
+++ b/node/Multicaster.cpp
@@ -107,7 +107,6 @@ restart_member_scan:
 void Multicaster::send(
 	const CertificateOfMembership *com,
 	unsigned int limit,
-	unsigned int gatherLimit,
 	uint64_t now,
 	uint64_t nwid,
 	const MulticastGroup &mg,
@@ -129,7 +128,7 @@ void Multicaster::send(
 			nwid,
 			com,
 			limit,
-			gatherLimit,
+			0,
 			src,
 			mg,
 			etherType,
@@ -143,25 +142,7 @@ void Multicaster::send(
 				break;
 		}
 	} else {
-		// If we don't already have enough members, send to the ones we have and then gather (if allowed within gather rate limit delay)
-		gs.txQueue.push_back(OutboundMulticast());
-		OutboundMulticast &out = gs.txQueue.back();
-
-		out.init(
-			now,
-			RR->identity.address(),
-			nwid,
-			com,
-			limit,
-			gatherLimit,
-			src,
-			mg,
-			etherType,
-			data,
-			len);
-
-		for(std::vector<MulticastGroupMember>::const_reverse_iterator m(gs.members.rbegin());m!=gs.members.rend();++m)
-			out.sendAndLog(*(RR->sw),m->address);
+		unsigned int gatherLimit = (limit - (unsigned int)gs.members.size()) + 1;
 
 		if ((now - gs.lastExplicitGather) >= ZT_MULTICAST_GATHER_DELAY) {
 			gs.lastExplicitGather = now;
@@ -178,11 +159,32 @@ void Multicaster::send(
 				outp.append((uint8_t)0);
 				mg.mac().appendTo(outp);
 				outp.append((uint32_t)mg.adi());
-				outp.append((uint32_t)((limit - (unsigned int)gs.members.size()) + 1)); // +1 just means we'll have an extra in the queue if available
+				outp.append((uint32_t)gatherLimit); // +1 just means we'll have an extra in the queue if available
 				outp.armor(sn->key(),true);
 				sn->send(RR,outp.data(),outp.size(),now);
 			}
+
+			gatherLimit = 0; // once we've done this we don't need to do it implicitly
 		}
+
+		gs.txQueue.push_back(OutboundMulticast());
+		OutboundMulticast &out = gs.txQueue.back();
+
+		out.init(
+			now,
+			RR->identity.address(),
+			nwid,
+			com,
+			limit,
+			gatherLimit,
+			src,
+			mg,
+			etherType,
+			data,
+			len);
+
+		for(std::vector<MulticastGroupMember>::const_reverse_iterator m(gs.members.rbegin());m!=gs.members.rend();++m)
+			out.sendAndLog(*(RR->sw),m->address);
 	}
 }