5 ms·
I'm using averages for both which should generally account for variations over time, but at any given moment the total percentage would change. I'm not educated
by packetlost 3y ago
I'm using averages for both which should generally account for variations over time, but at any given moment the total percentage would change. I'm not educated enough on the topic to know how much though. My guess is there's a large baseline energy cost to running a chiller system, while a modern servers have a fairly low idle power draw (see some of my sources, it's pretty interesting how far we've come in this department).
- sokoloff 3y agoCase 1a: A DC is using 60kW for equipment and 40kW for cooling Case 1b: Code efficiency of 5% improves the equipment to 57kW for equipment; I'd expect cooling to drop to around 38kW rather than remain at 40kW to remove that 57kW of heat load. If that's the case, a 5% improvement in equipment power draw is a 5% improvement in overall DC power draw, not a 3% (5% improvement on 60% of it).
- packetlost 3y agoA code efficiency improvement of 5% (represented as a 5% improvement in CPU utilization) does not equate to a 5% improvement in equipment power draw though. You at least need to factor in the percentage of an individual server's power draw that goes to the CPU, which is about 30% (again, on average). So a 5% equipment power draw improvement would need at least a 15% code efficiency improvement (0.05 / 0.3 = 0.1666), assuming you're CPU bound on whatever your code is doing. I factored in the average CPU load (50%) to account for this, but it's heavily application dependent.
- sokoloff 3y agoWhatever the percentage is for equipment applies closer to 1:1 than 0:1 to the cooling is my main point. I agree that it's not 1:1 from CPU to equipment.
- packetlost 3y agoYeah, that would make sense
- deleted 3y ago[deleted]