I was following the cpu_tuple_cost thread and wondering, if it could be
possible to make PQA style utility to calculate configuration-specific
values for planner cost constants. It could make use of output of
log_(statement|parser|planner|executor)_stats, tough I'm not sure if the
output contains anything useful for those purposes.
Otherwise it could just collect statements, run EXPLAIN ANALYZE for all
of them and then play with planner cost constants to get the estimated
values as close as possible to actual values. Something like Goal Seek
in Excel, if you pardon my reference to MS :).
Somewhat similar project seems to be pgautotune from pgFoundry, but it
only considers shared_buffers, sort_mem and vacuum_mem. And it seems to
use synthetic data instead of actual database and actual statements from
log. And it has been inactive for a while.
Tambet
