GitLab

* [test]: add a more general test case

- also rebalance the tests a bit

* added missing arg

* balance

* better checking

* balance

* make test smaller and faster

* make ddp results cached and enable sync_bn

* clean up

* fix tests

* changelog

* blance

* fix

* addressing comments
Co-authored-by: Min Xu <min.xu@acm.org>