cluster computing

[jproffer]

I'll try cpuminer next.

Well, cpuminer is nice since it not only creates significant load (unlike many other tools used for benchmarking) but also provides real performance numbers. And at the link above I provide a whole archive with tools and templates to simply measure/collect/graph the efficiency of performance (which is thermal) tuning. See the khash/s on the lower right corner:



Using RPi-Monitor you get also a history of measurements so you can easily compare. If I would setup a cluster I would immediately start to undervolt the individual cluster nodes (which requires testing for reliability and every board might behave different -- for this purpose Linpack is great) since this helps improving performance a lot due to throttling jumping in later.

Fun fact: as usual with benchmarking nearly all the times it goes wrong. Back when I had two Pine64+ here (I sent one of them to another Armbian dev, he received it yesterday and immediately gave it a go) I compared two different OS images by exchanging SD cards. One installation was approx. 5% faster. The only difference I found was one minor GCC update missing. And after updating GCC on the other installation performance was on par again.

The usual 'Casual benchmarking: you benchmark A, but actually measure B, and conclude you've measured C.'

   
It's been running cpuminer for about 30-40 minutes so far