Row level stats

It would be nice if PGAvd could receive row level stats without a large
hit to simple queries.

Ran a simple test. Calling pgstat_report_tabstat() at a frequency of
once per second reduces the time taken for row level stats to be
negligible:

500k select TRUE statements took:
6:50 with stats off
8:35 with row level stats on
6:52 with the below applied and row level stats on

Anyone object to delaying the submission of stats by that timeframe?
Are row level stats enough for PGAvd?

More or less the below for the change on line 1912 in postgres.c

currtme = GetCurrentAbsoluteTime();
if (lasttme < currtme)
{
pgstat_report_tabstat();
lasttme = currtme;
}

--
Rod Taylor <rbt(at)rbt(dot)ca>

PGP Key: http://www.rbt.ca/rbtpub.asc