3 ms·
While that's correct, it's misleading in the big picture. On full load, any machine hits thermal constraints, so, considering clock changes a problem, a deskto
by pizza234 5y ago
While that's correct, it's misleading in the big picture.
On full load, any machine hits thermal constraints, so, considering clock changes a problem, a desktop is problematic as well. A desktop will certainly have a higher ceiling, and/or a laptop may have too much of a low one, but it's incorrect to assume that the problem is inherent to laptops.
The solution is therefore, which is canonical in serious benchmarks and it's not mentioned, is to ensure that the machine runs on a fixed clock rate. This is easily accomplished, at least on desktops, by changing the BIOS. I wasn't personally able to do this from the O/S (Linux).
Using a machine without control on the clock (which a cloud one can be, even if bare metal) is subject to generate inaccurate benchmark results.
- celrod 5y agoDepending on the scaling governor you're using, you should be able to adjust behavior from the command line: https://www.kernel.org/doc/html/v4.12/admin-guide/pm/cpufreq.html https://www.kernel.org/doc/html/v4.12/admin-guide/pm/cpufreq... https://www.kernel.org/doc/html/v4.12/admin-guide/pm/intel_pstate.html https://www.kernel.org/doc/html/v4.12/admin-guide/pm/intel_p... E.g., if you're using the Intel pstate driver in active mode, you can disable turbo via: echo "1" | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo (and re-enable by writing "0".)
- pizza234 5y agoThanks! I'll check the reference document to search for something that works. In the past, I had tried (to no avail) with the `userspace` governor, `cpufreq-set`, `cpupower` and also `/sys/*/cpufreq/scaling_max_freq`; hopefully, I'll find other info in the document.