On Wed, Jun 10, 2020 at 6:04 PM David Rowley <dgrowle...@gmail.com> wrote: > > On Wed, 10 Jun 2020 at 17:39, David Rowley <dgrowle...@gmail.com> wrote: > > > > On Wed, 10 Jun 2020 at 17:21, Thomas Munro <thomas.mu...@gmail.com> wrote: > > > I also heard from Andres that he likes this patch with his AIO > > > prototype, because of the way request merging works. So it seems like > > > there are several reasons to want it. > > > > > > But ... where should we get the maximum step size from? A GUC? > > > > I guess we'd need to determine if other step sizes were better under > > any conditions. I guess one condition would be if there was a LIMIT > > clause. I could check if setting it to 1024 makes any difference, but > > I'm thinking it won't since I got fairly consistent results on all > > worker settings with the patched version. > > I did another round of testing on the same machine trying some step > sizes larger than 64 blocks. I can confirm that it does improve the > situation further going bigger than 64. >
Can we try the same test with 4, 8, 16 workers as well? I don't foresee any problem with a higher number of workers but it might be better to once check that if it is not too much additional work. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
