The chunk size for a specific collection is calculated according to the following rules in order of precedence:
- The collection specific chunk size maxChunkSizeBytes field in config.collection if set
- The global chunk size setting in config.settings.chunkSize if set
- The default global chunk size setting
So currently it is not straightforward for a user checking which is the currently configured chunk size setting for a specific collection.
My proposal is to expose such information in the collectionBalancerStatus output, taking into account the 3 rules listed above.