A number of statistics in WiredTiger are only non-zero or relevant for specific configurations of WiredTiger, e.g.:

• ASC / DSC
• Logging on / off
• Background compact, on / off

In theory we don't need to return a very large portion of statistics to MongoDB at any given time if we can determine which ones are relevant to the current WiredTiger configuration. This would require a substantial amount of work, and could be broken down into phases:

1. Define new sub-categories of stats, or tags, e.g. "asc", "dsc"
2. Categorize the stats
3. Update the statistics cursor implementation to only return stats from the relevant categories. 

A separate implementation method here would be to add or update the existing stat API which allows the user to chose what type of stats they would like, e.g. "fast", "all", "tree_walk". This API is somewhat confused though as it serves two purposes:

1. It controls whether some stats are gathered (the variable is populated) or not
2. It controls whether some stats are exported via the statistic cursor

Thus we could update the statistics cursor API to improve on this but it may introduce a lot more complexity than simply returning relevant statistics only.

Scope:

• Understand complexity of the current API
• Choose a path, break down into sub-tickets
• Implement