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strictnein

Sadly no note on how much that cost.

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220,000 cores of preemptible was about $2200/hr (I believe Drew is using n1-highcpu-32s).

Disclosure: I work on Google Cloud, launched Preemptible (and approved Drew's quota requests!)

That's a really nice info to share, i was thinking almost an order of magnitude higher, thank you.

The fuel bill per hour for the 737 going over my house right now is easily double $2200. I can visualise what is going on with a plane burning through fuel/money but with 220000 CPU cores it is all imaginary.

How big a house would be needed for such an array of 'cores'? How much electricity is required, and again can that be compared to aeroplanes, Teslas or even toasters?

Let's say you're using 2x 10 core CPUs per 1U PC, in a 42U rack. That's 840 cores per rack, 262 racks. You won't fit that in a house, you need a moderately large datacenter.

At 100W per CPU that's 22kW, which feels low; about a tenth of a Tesla and a fraction of a plane. That doesn't account for the cooling you'll need!

(You can probably do a lot better, but that's my piano tuners estimate)

I would be shocked if Google wasn't getting 2x 32 core CPUs per 1U at a minimum, which brings down your rack count a bit.

22kW of CPU heat would need 22kW of cooling. Refrigerated air conditioning is has about 1:3 thermal efficiency, so your cooling system will require ~7.5kW electricity to generate 22kW cooling capacity.

That makes about 30kW. At $0.15 / kWh we're talking about $4.5 per hour for the electricity.

Other costs dwarf the energy costs.

Note that 22kW is right about what a Tesla will consume cruising at highway speeds. So you could label that as "an efficient cruising car."

If it were 10 cores/CPU then 220,000 cores is 22,000 CPUs. At 100W per CPU that's 2,200,000W = 2.2MW. So more like a train than a Tesla!

So ~$300/hour in electricity.

Yes, and based on the $0.15/kWh comment, about $450/hour of electricity.

This is more in line with what I would have guessed for 220k cores.

Even if those were ARM cores (currently 192 cores/U @ 1.8 GHz), it would still take about 30 racks. ARM sucks at single-core performance, but it handles parallel workloads very well.

Actually, a 737-700 burns less than $2200 worth of fuel per hour, depending on operating weight, and how good a deal on the fuel the airline receives.

737-700 burns approximately 750 Gallons per hour at approximately $2.50/Gallon for Jet-A1 purchased wholesale. $1875/Hr for the fuel.

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