Don't hold memory used for sending indexes forever

model/model.go

@@ -563,31 +563,36 @@ func (m *Model) AddConnection(rawConn io.Closer, protoConn protocol.Connection)
 func sendIndexes(conn protocol.Connection, repo string, fs *files.Set) {
 	nodeID := conn.ID()
 	name := conn.Name()
+	var err error
 
 	if debug {
 		l.Debugf("sendIndexes for %s-%s@/%q starting", nodeID, name, repo)
 	}
 
-	initial := true
-	minLocalVer := uint64(0)
-	var err error
-
 	defer func() {
 		if debug {
 			l.Debugf("sendIndexes for %s-%s@/%q exiting: %v", nodeID, name, repo, err)
 		}
 	}()
 
+	minLocalVer, err := sendIndexTo(true, 0, conn, repo, fs)
+
 	for err == nil {
-		if !initial {
 		time.Sleep(5 * time.Second)
 		if fs.LocalVersion(protocol.LocalNodeID) <= minLocalVer {
 			continue
 		}
-		}
 
+		minLocalVer, err = sendIndexTo(false, minLocalVer, conn, repo, fs)
+	}
+}
+
+func sendIndexTo(initial bool, minLocalVer uint64, conn protocol.Connection, repo string, fs *files.Set) (uint64, error) {
+	nodeID := conn.ID()
+	name := conn.Name()
 	batch := make([]protocol.FileInfo, 0, indexBatchSize)
 	maxLocalVer := uint64(0)
+	var err error
 
 	fs.WithHave(protocol.LocalNodeID, func(f protocol.FileInfo) bool {
 		if f.LocalVersion <= minLocalVer {
@@ -623,21 +628,19 @@ func sendIndexes(conn protocol.Connection, repo string, fs *files.Set) {
 		return true
 	})
 
-		if initial {
+	if initial && err == nil {
 		err = conn.Index(repo, batch)
 		if debug && err == nil {
 			l.Debugf("sendIndexes for %s-%s/%q: %d files (small initial index)", nodeID, name, repo, len(batch))
 		}
-			initial = false
-		} else if len(batch) > 0 {
+	} else if len(batch) > 0 && err == nil {
 		err = conn.IndexUpdate(repo, batch)
 		if debug && err == nil {
 			l.Debugf("sendIndexes for %s-%s/%q: %d files (last batch)", nodeID, name, repo, len(batch))
 		}
 	}
 
-		minLocalVer = maxLocalVer
-	}
+	return maxLocalVer, err
 }
 
 func (m *Model) updateLocal(repo string, f protocol.FileInfo) {