Database on high load extremly bugly

Since Stash instance is under 500 users load, with ~1500 repos, in some of them over 10000 pull requests — database engine (Hibernate, i suppose) sometime is locked and fires an error.

For example, you merge pull request, it is merged success, but Activity failed to add into database and pull request has no Activity records that it was merged. Missed link to merge commit. Etc.

The same is for comments.

Will be nice to have spinlock in this place, to lock UI until database was released and update can be performed success. Do not stop trying if only error occurs once. Try again and again. Spin lock

Maybe some timeout really usefull in this situation, to avoid locking entire application to some reason. Bu, i think, that 99% problems will be solved by simple spinlocking for a twice loop step.