$queryStats
What changes in $queryStats compared with MongoDB and what your application has to do.
This difference is of the Different kind.
What MongoDB does
$queryStats gives its metrics per query shape.
What TeselaDB does
It gives the same main metrics with the same key; some are counted when the query's cursor ends.
What your application has to do
Use $queryStats to compare queries within the cluster, not with MongoDB's figures.