On 21 January 2014 21:19, Peter Geoghegan <p...@heroku.com> wrote: > On Tue, Jan 21, 2014 at 11:48 AM, Simon Riggs <si...@2ndquadrant.com> wrote: >> I agree with people saying that stddev is better than nothing at all, >> so I am inclined to commit this, in spite of the above. > > I could live with stddev. But we really ought to be investing in > making pg_stat_statements work well with third-party tools. I am very > wary of enlarging the counters structure, because it is protected by a > spinlock. There has been no attempt to quantify that cost, nor has > anyone even theorized that it is not likely to be appreciable.
OK, Kondo, please demonstrate benchmarks that show we have <1% impact from this change. Otherwise we may need a config parameter to allow the calculation. Thanks very much. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
