Wikistats broadly comes in two parts
- A Content and activity reports per wiki (html tables and charts based on the xml dumps)
- B Traffic reports

  Traffic reports are built from two sources

  -- B1 Domas' hourly aggregations per wiki, aggregated further into monthly totals per wiki (mobile/non-mobile,  normalized/non-normalized), grouped by project
     e.g. http://stats.wikimedia.org/EN/TablesPageViewsMonthlyCombined.htm

  -- B2 Sampled log lines (these days generated via hadoop)

      These sampled log lines are used for two types of reports (with some hybrids)

      --- B2a Breakdowns of traffic by geographic criteria (country, continent, N/S)
            http://stats.wikimedia.org/wikimedia/squids/SquidReportsCountriesLanguagesVisitsEdits.htm

      --- B2b Breakdowns of traffic by non geographic criteria (os, browser, mime type, target wiki, referer, etc)
            http://stats.wikimedia.org/cgi-bin/search_portal.pl?search=breakdown+of+traffic

My current proposal is on disabling B2b and hybrid reports like
http://stats.wikimedia.org/wikimedia/squids/SquidReportCountryData.htm