On 27/11/2019 22.56, Lux, Jim (US 337K) via Beowulf wrote: > With respect to "free cycles" in desktop computers - back in the day, 10-15 > years ago, a bunch of folks made measurements on cluster nodes of one sort or > another. As I recall, there *is* a power consumption change between full > load and not, but there's a significant "background load" that is more than > 50% of the total power consumption.
With current hardware, there is a significant difference (at least, assuming the "ipmi-dcmi --get-system-power-statistics" output is correct). On our skylake nodes ("standard 2-socket CPU nodes") idle power is about 50W, when running flat out about 400W. Somewhat older hardware is less good at saving power when idle, Westmere nodes consume about 100W idling. IIRC our old Istanbul Opterons (which we have already thrown away, so can't double-check) consumed about 170W when idle. -- Janne Blomqvist _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit https://beowulf.org/cgi-bin/mailman/listinfo/beowulf