I am running 8.3.7 on FreeBSD 7.0/amd64. It appears that at some point about 2 weeks ago statistics tracking ceased.
I have the following query which I use to track cache hits, and it is not being updated: SELECT pg_stat_database.datname, pg_stat_database.blks_read, pg_stat_database.blks_hit, round((pg_stat_database.blks_hit::double precision / (pg_stat_database.blks_read + pg_stat_database.blks_hit + 1)::double precision * 100::double precision)::numeric, 2) AS cachehitratio FROM pg_stat_database WHERE pg_stat_database.datname !~ '^(template(0|1)|postgres)$'::text ORDER BY round((pg_stat_database.blks_hit::double precision / (pg_stat_database.blks_read + pg_stat_database.blks_hit + 1)::double precision * 100::double precision)::numeric, 2) DESC; blks_hit and blks_read values have not changed. track_activities and track_counts is on. The result of the query is shown below, but the values remain static. Same is the case with values such as "sessions";1819965;219050729;99.18 "ishield";12291564297;38928261045;76.00