On Tue, Oct 8, 2024 at 8:34 PM Michael Paquier <mich...@paquier.xyz> wrote: > > On Mon, Oct 07, 2024 at 03:23:08PM -0700, Masahiko Sawada wrote: > > In the benchmark, I've applied the v20 patch set and 'master' in the > > result refers to a19f83f87966. And I disabled CPU turbo boost where > > possible. Overall, v20 patch got a similar or better performance in > > both COPY FROM and COPY TO compared to master except for on MacOS. > > I'm not sure that changes made to master since the last benchmark run by > > Tomas and Suto-san might contribute to these results. > > Don't think so. FWIW, I have been looking at the set of tests with > previous patch versions around v7 and v10 I have done, and did notice > a similar pattern where COPY FROM was getting slightly better for text > and binary. It did not look like only noise involved, and it was > kind of reproducible. As long as we avoid the function pointer > redirection for the per-row processing when dealing with in-core > formats, we should be fine as far as I understand. That's what the > latest patch set is doing based on a read of v21.
Yeah, what v21 patch is doing makes sense to me. > > > I'll try to investigate the performance regression that happened on MacOS. > > I don't have a good explanation for this one. Did you mount the data > folder on a tmpfs and made sure that all the workloads were > CPU-bounded? Yes, I used tmpfs and workloads were CPU-bound. > > > I think that other performance differences in my results seem to be within > > noises and could be acceptable. Of course, it would be great if others > > also could try to run benchmark tests. > > Yeah. At 1~2% it could be noise, but there are reproducible 1~2% > evolutions. In the good sense here, it means. In real workloads, COPY FROM/TO operations would be more disk I/O bound. I think that 1~2% performance differences that were shown in CPU-bound workload would not be a problem in practice. Regards, -- Masahiko Sawada Amazon Web Services: https://aws.amazon.com
