Saving frequency scaling in the data center

Posted May 21, 2020 19:21 UTC (Thu) by josh (subscriber, #17465)
Parent article: Saving frequency scaling in the data center

To what extent could this depend on whether the system is currently running on battery? If you're running on battery, you may want a default policy of "save as much power as possible", albeit that needs to not cause increased power usage overall on a workload (such as making something take 30% longer to save 5% power, which is not a win if you're trying to get that workload done before you run out of battery). If you're running on mains power (and you're not in the "large datacenter with substantial power and cooling costs that you're paying for" use case), you may want more affordances for performance.

Back in the say, making *anything* conditional on "running on battery" was seen as a mistake. Is that still true today, though? Might that help make defaults work for more people?

Saving frequency scaling in the data center

Posted May 22, 2020 10:26 UTC (Fri) by LtWorf (subscriber, #124958) [Link] (1 responses)

Unfortunately the workload of browsers is to take a lot of CPU permanently so that websites can run their useless js.

In the case of browsers, the entire idea of making the CPU running faster to get the work done sooner does not work, because it's just endless loops all over the place.

Saving frequency scaling in the data center

Posted May 24, 2020 0:10 UTC (Sun) by josh (subscriber, #17465) [Link]

That's a problem to be solved in browsers. The OS's job is to run the workloads given to it, and to attempt to balance power and performance in doing so.

Saving frequency scaling in the data center

Posted May 25, 2020 0:39 UTC (Mon) by marcH (subscriber, #57642) [Link]

> Back in the say (day?), making *anything* conditional on "running on battery" was seen as a mistake.

Weird. I love defaults that work in every case but power has obviously very different "prices" depending on the context:

1. Super expensive because I absolutely need my battery to last at least the day
2. Somewhat expensive because my data center charges me - yet I value happy customers more.
3. A bit "expensive" because I don't want to get up from the couch and look for my charger
4. Free because my data center doesn't charge me.
Etc.

OK, we probably don't want 5 or 10 different power settings like some Windows OEMs provide but two settings ("I care" vs "I don't care much") seems like a really bare minimum.