Think about keeping Ehcache 2 support

We are already thinking about it, hence the questions The question really boils down to (1) who is migrating it to the new SPI and (2) who is responsible for maintaining the upkeep of it. (1) is really a specialization of (2).

Why do you think people continue to use Ehcache 2 over 3? I have read that 3 has worse performance compared to 2 - is that why?

I think you are right and I will start with hibernate-jcache. But that will not take overly long. And 5.3 release is pressing, so this needs to be resolved soon-ish - next week at the very latest.