Amina Guermouche (Storm)

Greetings, everyone!

Have you been feeling low on energy? Taking too long to solve any problems? Have you tried combining uncore frequency and dynamic power capping? No? Well, maybe you can join us in our next team seminar by Amina Guermouche to learn more about this subject!

You can join us on June 14 (Tuesday) at 11 am in room Grace Hopper 2 or online.

Speaker

Amina Guermouche (Storm)

When

Tuesday, June 14, 2022 at 11 am.

Where

room Grace Hopper 2 or online (Zoom link below)

Title

Combining Uncore Frequency and Dynamic Power Capping to Improve Power Savings

Abstract

The US Department of Energy sets a limit of 20 to 30 MW for future exascale machines. In order to control their power consumption, modern processors provide many features. Power capping and uncore frequency scaling are examples of such features which allow to limit the power consumed by a processor.

In this talk, I will first present some results on uncore frequency scaling, then I will describe a solution to combine dynamic power capping to uncore frequency scaling. We propose DUFP, an extension of DUF, an existing tool which dynamically adapts uncore frequency. DUFP dynamically adapts the processor power cap to the application needs. Finally, just like DUF, DUFP can tolerate performance loss up to a user-defined limit. With a controlled impact on performance, DUFP is able to provide power savings with no energy loss.

The evaluation of DUFP shows that it manages to stay within the user-defined slowdown limits for most of the studied applications. Moreover, combining uncore frequency scaling to power capping: (i) improves power consumption by up to 13.98 % with additional energy savings for applications where uncore frequency scaling has a limited impact, (ii) improves power consumption by up to 7.90 % compared to using uncore frequency scaling by itself and (iii) leads to more than 5 % power savings at 5 % tolerated slowdown with no energy loss for most applications.