Regenerate summaries
Wakapi improves its efficiency and speed by automatically aggregating individual heartbeats to summaries on a per-day basis. That is, historic summaries, i.e. such from past days, are generated once and only fetched from the database in a static fashion afterwards, unless you pass &recompute=true with your request.
If, for some reason, these aggregated summaries are faulty or preconditions have change (e.g. you modified language mappings retrospectively), you may want to re-generate them from raw heartbeats.
Note: Only run this action if you know what you are doing. Data might be lost is case heartbeats were deleted after the respective summaries had been generated.