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Signed-off-by: Tomasz Pietrek <tomasz@nats.io>

server/stream.go

@@ -213,7 +213,7 @@ type stream struct {
 	lseq      uint64
 	lmsgId    string
 	consumers map[string]*consumer
-	numFilter int
+	numFilter int // number of filtered consumers
 	cfg       StreamConfig
 	created   time.Time
 	stype     StorageType
@@ -4625,7 +4625,7 @@ func (mset *stream) numConsumers() int {
 func (mset *stream) setConsumer(o *consumer) {
 	mset.consumers[o.name] = o
 	if o.subjf != nil {
-		mset.numFilter += len(o.subjf)
+		mset.numFilter++
 	}
 	if o.cfg.Direct {
 		mset.directs++
@@ -4727,12 +4727,11 @@ func (mset *stream) swapSigSubs(o *consumer, newFilters []string) {
 	mset.mu.Lock()
 	defer mset.mu.Unlock()
 
-	mset.numFilter += len(newFilters)
-
-	for range o.subjf {
-		if mset.numFilter > 0 {
-			mset.numFilter--
-		}
+	if mset.numFilter > 0 && len(o.subjf) > 0 {
+		mset.numFilter--
+	}
+	if len(newFilters) > 0 {
+		mset.numFilter++
 	}
 }
 
@@ -4791,11 +4790,9 @@ func (mset *stream) Store() StreamStore {
 func (mset *stream) partitionUnique(partitions []string) bool {
 	for _, partition := range partitions {
 		for _, o := range mset.consumers {
-
 			if o.subjf == nil {
 				return false
 			}
-
 			for _, filter := range o.subjf {
 				if subjectIsSubsetMatch(partition, filter.subject) ||
 					subjectIsSubsetMatch(filter.subject, partition) {