RE: Performance regressions introduced via Revert "cpuidle: menu: Avoid discarding useful information" on 5.15 LTS

["Doug Smythies" <dsmythies@telus.net>]

On 2026.02.10 00:57 Christian Loehle wrote:
> On 2/10/26 08:02, Sergey Senozhatsky wrote:
>> On (26/02/05 07:15), Christian Loehle wrote:
>> [..]
>>> @Doug given this is on Chromebooks base=84.5 and revert=59.5 doesn't necessarily mean
>>> 29.6% decrease in system performance in a traditional throughput sense.
>>> The "benchmark" might me measuring dropped frames, user input latency or what have you.
>>> Nonetheless @Sergey do feel free to expand.
>> 
>> I'm not on the performance team and I don't define those metrics, so
>> I can't really comment.  But frame drops during Google Docs scrolling,
>> for instance, or typing is a user visible regression, that people tend
>> to notice.
>
> Yeah I guess that was my point already, i.e. it isn't implausible that
> e.g. a frequency reduction from 2.2GHz to 2.0GHz (-10%) might result in
> double the number of dropped frames (= score reduction of 50%).
> Everything just an example but don't be thrown off by the 29.6% reduction in
> score and expect to go looking for -29.6% cpu frequency (like you would expect
> for many purely cpubound benchmarks).

Thanks for the inputs. Agreed.
In my defense, I was just attempting to extract whatever I could from
the very limited data we had.

... Doug