On 03/04/2018 03:20 AM, Thomas Munro wrote: > Hi, > > I saw a one-off failure like this: > > QUERY PLAN > -------------------------------------------------------------------------- > Aggregate (actual rows=1 loops=1) > ! -> Nested Loop (actual rows=98000 loops=1) > -> Seq Scan on tenk2 (actual rows=10 loops=1) > Filter: (thousand = 0) > Rows Removed by Filter: 9990 > ! -> Gather (actual rows=9800 loops=10) > Workers Planned: 4 > Workers Launched: 4 > -> Parallel Seq Scan on tenk1 (actual rows=1960 loops=50) > --- 485,495 ---- > QUERY PLAN > -------------------------------------------------------------------------- > Aggregate (actual rows=1 loops=1) > ! -> Nested Loop (actual rows=97984 loops=1) > -> Seq Scan on tenk2 (actual rows=10 loops=1) > Filter: (thousand = 0) > Rows Removed by Filter: 9990 > ! -> Gather (actual rows=9798 loops=10) > Workers Planned: 4 > Workers Launched: 4 > -> Parallel Seq Scan on tenk1 (actual rows=1960 loops=50) > > > Two tuples apparently went missing. > > Similar failures on the build farm: > > https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=okapi&dt=2018-03-03%2020%3A15%3A01 > https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=locust&dt=2018-03-03%2018%3A13%3A32 > https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=prairiedog&dt=2018-03-03%2017%3A55%3A11 > > Could this be related to commit > 34db06ef9a1d7f36391c64293bf1e0ce44a33915 or commit > 497171d3e2aaeea3b30d710b4e368645ad07ae43? >
I think the same failure (or at least very similar plan diff) was already mentioned here: https://www.postgresql.org/message-id/17385.1520018...@sss.pgh.pa.us So I guess someone else already noticed, but I don't see the cause identified in that thread. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
