WiredTiger fragmentation

With the wiredtiger engine I've noticed db.collection.stats() output is different. In the past this out output could be used to calculate fragmentation. How would one calculate fragmentation with wiredtiger?

Fragmentation concept isn't applicable to WiredTiger the same way it's applicable to MmapV1.    WiredTiger does ongoing compaction and reuse of space automatically.   Can you describe a specific workload and what you're seeing in terms of space usage that may concern you and consider possibility of fragmentation?

Or is this more general question?

Just a general question. Thanks



The more I learn about WiredTiger, the more it is looking like a real win for MongoDB and our usage of it.