[rystsov]

The mess is mostly the result of the mismatch between the classic database transactional model and kafka transactional model (G0 anomaly). If you read the documentation without the database background it seems ok, but when you notice the differences between the models it becomes hard to understand if it's a bug or property of the Kafka protocol.

There is a lot of research happening around this area even in the database world. The list of the isolation levels isn't final and some of the recent developments include PC-PSI and NMSI which also seem to "violate" the order. I hope one day we get the formal academic description of the Kafka model. It looks very promising.

[aphyr]

I agree--rystsov has covered this well here and in other parts of the thread. I just want to add that some of the Kafka documentation did claim writes were isolated (where other Kafka documentation contradicts that claim!) so it's possible that depending on which parts of the docs users read, they might expect that G0 was prohibited. That's why this report discusses it in such detail. :-)

[btown]

Are there good research groups or journals to follow to keep apprised of the state of the art here?

[rystsov]

I've created this list a while ago https://github.com/redpanda-data/awesome-distributed-transac.... Maybe it's time to update it.

Usually I start with a couple of seed papers then follow the references, look at the other papers the authors wrote. When a phd student explores an area they write several paper on the topic so there is a lot material to read. But the real gem is the thesis, it has depth, context and a lot of links to other work in the area.

[btown]

Thank you for putting this together!