Joe Conway <m...@joeconway.com> writes: > On 03/05/2018 11:19 AM, Tom Lane wrote: >> Joe, I wonder if you could add "log_autovacuum_min_duration = 0" to >> rhinoceros' extra_config options, temporarily? Correlating that log >> output with the log_statement output from the test proper would let >> us confirm or deny whether it's autovacuum.
> Done just now. Do you want me to force a run? Both of these runs https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=rhinoceros&dt=2018-03-05%2020%3A35%3A00 https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=rhinoceros&dt=2018-03-05%2021%3A45%3A02 appear to exonerate autovacuum, and the second seems to destroy the behind-the-scenes-ANALYZE theory entirely, since there was no change in the outputs of the extra instrumentation queries. (In theory there's a window for ANALYZE to have occurred in between, but that's not very credible.) So you can revert the rhinoceros config change if you like --- thanks for making it so quickly! Meanwhile, I'm back to wondering what could possibly have affected the planner's estimates, if pg_proc and pg_statistic didn't change. I confess bafflement ... but we've now eliminated the autovacuum- did-it theory entirely, so it's time to start looking someplace else. I wonder if something in the postgres_fdw remote join machinery is not as deterministic as it should be. regards, tom lane
