This came out of the discussion on the PR for WT-11010. Don raised a good point that WiredTiger should name the chunk cache file automatically. I don't think it should automatically be in the WiredTiger home directory since it'd be too easy for a real-world user to put the IO-heavy chunk cache file on the same volume as WiredTiger's data files and kill performance. But that's not the last word on the topic, and we can discuss that further as part of this ticket.