On Thu, Feb 22, 2018 at 12:35 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Robert Haas <rh...@postgresql.org> writes: >> Charge cpu_tuple_cost * 0.5 for Append and MergeAppend nodes. > > This seems to have produced some plan instability in the buildfarm.
I was worried about that. Looking at it now. I wish we had some way to figure out whether a given plan was likely to be unstable on the buildfarm other than committing it and seeing what happens. It's surprisingly difficult to write non-trivial tests that produce consistent EXPLAIN output, and annoyingly time-consuming to try to figure out why they don't. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
