Tech Tip #56: Look up what your job actually used

Your cluster already records the energy of every job.

Video created by explainapaper.com

The problem

Researchers see wall-clock time and core-hours, but many schedulers also record energy per job, and almost nobody looks.

The fix you can use today

  • Check whether your scheduler records job energy (for example sacct on Slurm).
  • Compare energy per result between code versions and settings.
  • Estimate before you run with a calculator for bigger campaigns.

The UK's ARCHER2 supercomputer lets users look up the energy of every job. GreenCode is exploring checks like this for jobs on shared clusters.

Tools that help

How GreenCode helps

GreenCode helps tackle this by measuring research code's energy before and after a change, pointing to the code behind each hotspot, and checking that the optimised code still gives the same results. More on this.

Tags

#hpc#measurement#research-software

Sources

Transcript

Your cluster may already record the energy of every job. Researchers watch run time and core hours. But many job schedulers also record the energy each job used. And almost nobody looks. You cannot cut what you never look at. Here is the fix you can use today. First, check if your scheduler records job energy. On Slurm, energy accounting records it, and the sacct command shows it. Then compare energy per result between versions, using tools like nf-co2footprint for Nextflow. For a big campaign, estimate before you run, using the Green Algorithms calculator. The UK's ARCHER2 supercomputer lets users look up the energy of every job. GreenCode is exploring checks like this for jobs on shared clusters. GreenCode helps tackle this by measuring research code's energy before and after a change. It points to the code behind each hotspot, and checks the answers stay the same. That was GreenCode Tech Tip number fifty-six. Follow for the next tip, and find more on greencode.ai/tech-tips.

All GreenCode Tech Tips · All GreenCode videos

  • Tip #56
  • For Ops and infrastructure
  • Length 1:08
  • Category HPC, embedded, mobile and games
GreenCode

Want this checked on your own system? Talk to the GreenCode team.

Get in touch