tillrohrmann commented on a change in pull request #7061: [FLINK-10827][tests] Add test for duplicate() to SerializerTestBase URL: https://github.com/apache/flink/pull/7061#discussion_r232467908
########## File path: flink-core/src/main/java/org/apache/flink/api/java/typeutils/runtime/PojoSerializer.java ########## @@ -181,11 +181,13 @@ public boolean isImmutableType() { } } - if (stateful) { - return new PojoSerializer<T>(clazz, duplicateFieldSerializers, fields, executionConfig); - } else { - return this; + if (!stateful) { + // as a small memory optimization, we can share the same object between instances + duplicateFieldSerializers = fieldSerializers; } + + // we must create a new instance, otherwise the subclassSerializerCache can create concurrency problems Review comment: I'm wondering whether the statefulness check is simply wrong. Since the `PojoSerializer` could also use a subclass serializer we should also check `subclassSerializerCache` and `registeredSerializers` for statefulness. However, the way this is done currently by duplicating and checking for referential equality might be quite inefficient... ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services