On Thu, Oct 26, 2017 at 02:45:15PM -0500, Justin Pryzby wrote: > On Tue, Oct 24, 2017 at 04:15:59PM +0200, johannes graën wrote: > > Hi Pavel, *, > > > > you were right with ANALYZing the DB first. However, even after doing > > so, I frequently see Seq Scans where an index was used before. This > > usually cooccurs with parallelization and looked different before > > upgrading to 10. I can provide an example for 10 [1], but I cannot > > generate a query plan for 9.6 anymore. > > > > Any ideas what makes the new version more seqscanny? > > Is it because max_parallel_workers_per_gather now defaults to 2 ? > > BTW, I would tentatively expect a change in default to be documented in the > release notes but can't see that it's. > 77cd477c4ba885cfa1ba67beaa82e06f2e182b85 Oops, you are correct. The PG 10 release notes, which I wrote, should have mentioned this. :-( https://www.postgresql.org/docs/10/static/release-10.html -- Bruce Momjian <bruce@xxxxxxxxxx> http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription +
