On 7 April 2018 at 15:41, Tom Lane <t...@sss.pgh.pa.us> wrote: > David Rowley <david.row...@2ndquadrant.com> writes: >> Sounds like you're saying that if we have too many alternative files >> then there's a chance that one could pass by luck. > > Yeah, exactly: it passed, but did it pass for the right reason? > > If there's just two expected-files, it's likely not a big problem, > but if you have a bunch it's something to worry about.
Right, I suggest we wait and see if all members go green again as a result of 40e42e1024c, and if they're happy then we could maybe leave it as is with the 2 alternatives output files. If there are some other variations that crop up, then we can think harder about what we can do to improve the coverage. I don't particularly think it matters which hash partition a tuple goes into, as long as the hash function spreads the values out enough and most importantly, the pruning code looks for the tuple in the partition that it was actually inserted into in the first place. Obviously, we also want to ensure we never do anything which would change the matching partition in either minor or major version upgrades too. -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services