On Wed, Mar 1, 2017 at 6:44 PM, Ashutosh Sharma <ashu.coe...@gmail.com> wrote:
> On Wed, Mar 1, 2017 at 5:29 PM, Simon Riggs <si...@2ndquadrant.com> wrote: > > > > On 1 March 2017 at 04:50, Ashutosh Sharma <ashu.coe...@gmail.com> wrote: > >> > >> On Tue, Feb 28, 2017 at 11:44 PM, Simon Riggs <si...@2ndquadrant.com> > wrote: > >>> > >>> On 28 February 2017 at 11:34, Ashutosh Sharma <ashu.coe...@gmail.com> > wrote: > >>> > >>>> > >>>> So, Here are the pgbench results I got with > >>>> 'reduce_pgxact_access_AtEOXact.v2.patch' > on a read-write workload. > >>> > >>> > >>> Thanks for performing a test. > >>> > >>> I see a low yet noticeable performance gain across the board on that > workload. > >>> > >>> That is quite surprising to see a gain on that workload. The main > workload we have been discussing was the full read-only test (-S). For that > case the effect should be much more noticeable based upon Andres' earlier > comments. > >>> > >>> Would it be possible to re-run the test using only the -S workload? > Thanks very much. > >> > >> > >> Okay, I already had the results for read-oly workload but just forgot > to share it along with the results for read-write test. Here are the > results for read-only > >> test, > > > > > > Thanks for conducting those comparisons. > > > > So we have variable and sometimes significant gains, with no regressions. > > > > By the shape of the results this helps in different places to the > alignment patch. Do we have evidence to commit both? > > Well, We have seen some regression in read-write test with pgxact > alignment patch - [1]. I may need to run the test with both the > patches to see the combined effect on performance. > > [1] - https://www.postgresql.org/message-id/CAE9k0Pk%2BrCuNY% > 2B7O5XwVXHPuki9t8%3DM7jr4kevxw-hdkpFhS2A%40mail.gmail.com > I agree. Probably Simon's patch for reducing pgxact access could negate regression in pgxact alignment patch. Ashutosh, could please you run read-write and read-only tests when both these patches applied? ------ Alexander Korotkov Postgres Professional: http://www.postgrespro.com The Russian Postgres Company