WT-4438, we determined that any statistics that do not use atomic increment may be inaccurate. For many cases we don't care about a fractional percentage drift. But in particular when a statistic holds a counter, and the drift can accumulate in one direction, we may care.
A check of the source tree looking for matches of STAT.*DECR should identify most or all cases where a statistic value represents a resource count.
For connection-wide statistics counters, we have:
and for statistics that are per-data source, we have:
We should fix these to use the STAT.*ATOMIC macros, or document that they may accumulate drift.