On Tue, Oct 2, 2018 at 7:08 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > > Amit Kapila <amit.kapil...@gmail.com> writes: > > I think if we do Analyze on the table after populating rows, it should > > use just one worker and that should be sufficient to hit the case > > being discussed. I would like to change the test so that it uses just > > one worker. > > I thought that adding an ANALYZE would make the test be net slower, not > faster; ANALYZE isn't free, even on just a row or so. >
Hmm, I am curious to know what is your theory behind this? I was under impression that spawning two additional workers would cost more than Analyze. > Also, I believe > that coding the test this way makes the leader send the param values to > multiple workers, which would flush out any problems with serializing a > value multiple times. As against that, there's a hazard that the number > of workers might not be stable ... Yeah, I was actually more worried about instability part, but now I have tested it on both windows and centos machine and the test passes, so I am okay with that. However, I feel if we want to go with that, there is actually no need of statement "SET force_parallel_mode=1". That statement is required to force parallelism on such a small table. It won't harm, but is misleading and in future people will try to copy it in other tests > but it seems like we have lots of > other occurrences of that same hazard elsewhere in this test script. > Right. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
