diff --git a/lib/persistedmap/persistedmap.go b/lib/persistedmap/persistedmap.go
index 06b6e406..1daa6e7d 100644
--- a/lib/persistedmap/persistedmap.go
+++ b/lib/persistedmap/persistedmap.go
@@ -61,11 +61,12 @@ func (p *PersistedMap) flushRoutine() {
 }
 
 func (p *PersistedMap) flush() error {
+	p.mu.Lock()
+
 	if !p.shouldSave {
 		return nil
 	}
 
-	p.mu.Lock()
 	defer p.mu.Unlock()
 
 	file, err := os.Create(p.filePath)