Completely unrelated thought: currently the API is more or less synchronous. For reads from the cache it makes sense, but during the flush, we usually want to update multiple entities in parallel, as the update takes a long time (due to RPC latency). Have you thought about some support for asynchronous operations? E.g. even if the implementation stored a CompletableFuture internally, waiting for the remote update to finish, there's no hook when the commit would wait until everything is completed, unless we directly register a synchronization on the transaction.