> > > > I repeated some tests in a more isolated environment and posted the > > results here: > > https://discourse.ubuntu.com/t/enable-low-latency-features-in-the-generic-ubuntu-kernel-for-24-04/42255 > > > > Highlights: > > > > - stress-ng --matrix seems quite unpredictable to be used a benchmarks > > in this scenario (the bogo-ops/s are very susceptible to any kind of > > interference, so even if in the long runs NO_HZ_FULL still seems to > > provide some benefits looking at the average, we also need to > > consider that there might be a significant error in the measurements, > > standard deviation was pretty high) > > > > - fio doing short writes (in page cache) seems to perform like 2x > > better in terms of iops with nohz_full, respect to the other cases > > and it performs 2x slower with large IO writes (not sure why... need > > to investigate more) > > > > - with lazy RCU enabled hrtimer_interrupt() takes like 2x more to > > return, respect to the other cases (is this expected?) > > This last is surprising at first glance, but I could be missing > something. Joel, Uladzislau, thoughts? > Could you please share the steps how you run "fio" tests? -- Uladzislau Rezki
