> On Jan 23, 2026, at 09:18, Andres Freund <[email protected]> wrote: > > Hi, > > I haven't yet looked at the new version of the patch, but I ran your benchmark > from upthread (fwiw, I removed the sleep 10 to reduce runtimes, the results > seem stable enough anyway) on two intel machines, as you mentioned that you > saw a lot variation in Azure. > > For both I disabled turbo boost, cpu idling and pinned the backend to a single > CPU core. > > There's a bit of noise on "awork3" (basically an editor and an idle browser > window), but everything is pinned to the other socket. "awork4" is entirely > idle. > > > Looks like overall the results are quite impressive! Some of the extra_cols=0 > runs saphire rapids are a bit slower, but the losses are much smaller than the > gains in other cases. > > > I think it'd be good to add a few test cases of "incremental deforming" to the > benchmark. E.g. a qual that accesses column 10, but projection then deforms up > to 20. I'm a bit worried that e.g. the repeated first_null_attr() > computations could cause regressions. > > > Greetings, > > Andres Freund > <deform_bench.csv>
Today I ran the benchmark on my MacBook M4 against 3 versions (all without assert and with -O2): 1) Master (f9a468c664a) 2) Master + v4 3) Master + v4 + My tweak (first_null_attr immediately returns 0 when natts == 0) Overall, v4 shows significant improvements across most configuration combinations. In the best case, v4 is about 43% faster than master. The tweak version is only slightly faster than v4. In the best case, the tweak achieves an additional ~3.5% improvement over v4. Note that the MacBook is my working laptop. I didn’t actively work on it while the tests were running, but it was still not fully idle, as some other applications (Email, VScode, etc.) were running in the background. That said, I suppose this is still fair for the three rounds of test runs. See the attached Excel sheet for details. Best regards, -- Chao Li (Evan) HighGo Software Co., Ltd. https://www.highgo.com/
pgbench_comparison_chao_li_mac_m4.xlsx
Description: MS-Excel 2007 spreadsheet
