Handler map doesn't need to be mutable.
@@ -70,7 +70,7 @@ private:
const ssize_t _defaultSerializedSize;
const bool _ignoreMaxBytes;
- mutable PersistenceHandlerMap _handlers;
+ PersistenceHandlerMap _handlers;
vespalib::Lock _lock;
Iterators _iterators;
vespalib::Lock _iterators_lock;
