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The Risks and Rewards of Warmer Data Centers
1sockchuck writes "The risks and rewards of raising the temperature in the data center were debated last week in several new studies based on real-world testing in Silicon Valley facilities. The verdict: companies can indeed save big money on power costs by running warmer. Cisco Systems expects to save $2 million a year by raising the temperature in its San Jose research labs. But nudge the thermostat too high, and the energy savings can evaporate in a flurry of server fan activity. The new studies added some practical guidance on a trend that has become a hot topic as companies focus on rising power bills in the data center."
1. Get a thermostat you can control with a computer
2. Give the computer inputs of temperature and energy use, and output of heating/cooling
3. Write a program to minimize energy use (genetic algorithm?)
4. Profit!!
Possible problem: do we need to factor in some increased wear & tear on the machines for higher temperatures? That would complicate things.
And yet the temperature here measured in F gets negative every winter. And where I previously lived it got above 100F every summer (and it also does where I am now, but only a day or three each year).
But in both those places a temperature of 0C was the freezing point of water, and 100C the boiling point. Yes that 100C one isn't so useful in terms of daily temperature, the 0C is though since whether water will freeze or not is the main transition point in daily temperature.
If there is a failure of AC ... that is, either Air Conditioning OR Alternating Current, you can see a rapid rise in temperature. With all the systems powered off, the latent heat inside the equipment, which is much higher than the room temperature, emerges and raises the room temperature rapidly. And if the equipment is still powered (via UPS when the power fails), the rise is much faster.
In a large data center I once worked at, with 8 mainframes and 1800 servers, power to the entire building failed after several ups and downs in the first minute. The power company was able to tell us within 20 minutes that it looked like a "several hours" outage. We didn't have the UPS capacity for that long, so we started a massive shutdown. Fortunately it was all automated and the last servers finished their current jobs and powered off in another 20 minutes. In that 40 minutes, the server room, normally kept around 17C, was up to a whopping 33C. And even with everything powered off, it peaked at 38C after another 20 minutes. If it weren't so dark in there I think some people would have been starting a sauna.
We had about 40 hard drive failures and 12 power supply failures coming back up that evening. And one of the mainframes had some issues.
now we need to go OSS in diesel cars
I think we're spending way too much time trying to 'cool' things that do not, in fact, need to be cooler than outside. Nowhere on earth is so hot that servers won't run, unless you've built a server room over an active volcano or something.
All we actually need to do is remove the heat from the servers to the air, and then keep swapping the air with the outside.
Which happens automatically if you let heat out the top and air in the bottom. Even if you have to condition the incoming air to remove moisture, that's cheaper than actually 'cooling' AC. So the second part, replacing the room air, is easy.
As for the first, I've always wondered why they don't use chimney-like devices to generate wind naturally and send it though server racks, instead of fans. I think all the heat in a server room could actually, on exit, suck incoming air in fast enough to cool computers if it actually hit the right places on the way in.
Heck, this would apply anyway. Instead of having AC vent into server rooms, why not have AC vent into server racks? Hook up the damn AC to the fan vent on each server, blow cold air straight in. The room itself could end not cold at all.
If corporations are people, aren't stockholders guilty of slavery?