Linux Plumbers Conf 2013

One Line Summary

Abstract

As battery-powered embedded devices move towards multicore processors, multicore energy efficiency is becoming critically important. To this end, ARM recently announced its big.LITTLE architecture, featuring a multicore chip with both high-performance processors and high-efficiency processors running a single instance of the Linux operating system. Prior work has shown the benefits of running performance-critical code on the high-performance processors, while confining other processing to the high-efficiency processors. This paper builds on this work by showing that for some important mobile workloads, pre-existing Linux-kernel tuning parameters originally designed for real time, high-performance computing, and SMP energy efficiency can further reduce the amount of non-performance-critical code running on the high-performance processors, resulting in energy efficiency gains in excess of 10%.

Presentation Materials

Speaker

• 

  Paul McKenney

  IBM Linux Technology Center
  • Website: http://www.rdrop.com/users/paulmck
  • Blog: http://paulmck/livejournal.com

  Biography

  Paul E. McKenney has been coding for almost four decades, more than half of that on parallel hardware, where his work has earned him a reputation among some as a flaming heretic. Over the past decade, Paul has been an IBM Distinguished Engineer at the IBM Linux Technology Center. Paul maintains the RCU implementation within the Linux kernel, where the variety of workloads present highly entertaining performance, scalability, real-time response, and energy-efficiency challenges. Prior to that, he worked on the DYNIX/ptx kernel at Sequent, and prior to that on packet-radio and Internet protocols (but long before it was polite to mention Internet at cocktail parties), system administration, business applications, and real-time systems. His hobbies include what passes for running at his age along with the usual house-wife-and-kids habit.

  Sessions

  • * But What About Concurrent Updates?
    • Title: But What About Concurrent Updates?
    • Microconference: Scaling
    • Time: 4:15pm
    • One Line Summary:

      We need mechanisms that do for update-mostly workloads that what RCU does for read-mostly workloads.

    • slides
    • Speakers: Paul McKenney
  • * Improving Energy Efficiency On Asymmetric Multiprocessing Systems
    • Title: Improving Energy Efficiency On Asymmetric Multiprocessing Systems
    • Microconference: Power-efficient Scheduling
    • One Line Summary:

      Energy-efficiency benefits of extended idle and RCU callback offloading.

    • slides
    • Speakers: Paul McKenney