Improve trash cleanup performance by using emptyDir?

[polyrabbit]

What would you like to be added: Trash files are flattened into hourly buckets, and CleanupTrashBefore deletes those entries one at a time sequentially. It's better to have it use emptyDir so that the max-deletes concurrency applies to trash purging as well?

Why is this needed: Trash cleanup is too slow, and max-deletes doesnot help.