On Wed, Sep 20, 2017 at 9:46 PM, Mithun Cy <mithun...@enterprisedb.com> wrote: > I think there is some confusion above results is for pgbench simple update > (-N) tests where cached snapshot gets invalidated, I have run this to check > if there is any regression due to frequent cache invalidation and did not > find any. The target test for the above patch is read-only case [1] where we > can see the performance improvement as high as 39% (@256 threads) on > Cthulhu(a 8 socket numa machine with 64 CPU cores). At 64 threads ( = CPU > cores) we have 5% improvement and at clients 128 = (2 * CPU cores = > hyperthreads) we have 17% improvement. > > Clients BASE CODE With patch %Imp > > 64 452475.929144 476195.952736 5.2422730281 > > 128 556207.727932 653256.029012 17.4482115595 > > 256 494336.282804 691614.000463 39.9075941867
Oh, you're right. I was confused. But now I'm confused about something else: if you're seeing a clear gain at higher-client counts, why is Jesper Pederson not seeing the same thing? Do you have results for a 2-socket machine? Maybe this only helps with >2 sockets. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
