Hi, On 2025-08-15 15:42:10 -0400, Peter Geoghegan wrote: > On Fri, Aug 15, 2025 at 3:38 PM Andres Freund <and...@anarazel.de> wrote: > > I see absolutely no effect of the patch with shared_buffers=1GB and a > > read-only scale 200 pgbench at 40 clients. What data sizes, shared buffers > > etc. were you testing? > > Just to be clear: you are testing with both the index prefetching > patch and your patch together, right? Not just your own patch?
Correct. > My shared_buffers is 16GB, with pgbench scale 300. So there's actually no IO, given that a scale 300 is something like 4.7GB? In that case my patch could really not make a difference, neither of the changed branches would ever be reached? Or were you testing the warmup phase, rather than the steady state? Greetings, Andres Freund
