jlj7 might be right, but at a guess, what you’re seeing is due to the fact that the raft data is stored in BoltDB data files, which are prone to containing a lot of “garbage”. That is, a 100MB bolt file might contain only 10MB of active data, and 90MB of unused data that may be overwritten in future. It doesn’t aggressively free up that space because it would require expensive disk operations - better to waste a bit of disk space than provide slow performance.