Too Hot for Humans, But Google Servers Keep Humming

http://www.datacenterknowledge.com/archives/2012/03/23/too-hot-for-humans-but-google-servers-keep-humming/

by cd34 • 14 years ago

118 82 14 years ago

1point2• 14 years ago

In the picture it sure does look like a row of evaporative coolers - there was no mention of them in the article - so maybe I'm wrong.

cd347• 14 years ago

Free air cooling uses evaporative coolers. They are not running chillers. Belgium also has a water treatment center bringing in water from an industrial canal for their coolers and thus runs on 100% recycled water.

In Finland, they run heat exchangers with water from the Baltic Sea, again, a chiller-less data center.

Document from Google that talks about their cooling: http://www.google.com/about/datacenters/inside/efficiency/co...

bengl3rt2• 14 years ago

Did anyone else think of the scene in Sunshine where Chris Evans gets stuck under the computer that's being lowered into fluid and freezes to death?

The mechanism for making "the hot aisle" temporarily habitable fails, you get stuck on/in something and can't get out in time.... Life imitates art.

cperciva3• 14 years ago

I think you're overstating the dangers a bit. A hot aisle might be uncomfortable and not a place you'd want to spend many hours, but it isn't going to kill you quickly. If by some series of amazing coincidences you managed to get stuck in one with no way to call for help, you could just start unplugging servers until someone came to investigate and rescue you.

mmmooo2• 14 years ago

speaking as someone who has been inside a "hot" datacenter of a few thousand servers (after a failed ac system which didn't trip the alarms for a few hours), uncomfortable does not really begin to cover it. The extremely dry, hot air was quiet difficult to breathe, and being inside for more then a couple of minutes at a time was pretty much impossible. Definitely not the same experience as sitting in a hot aisle. It has been a number of years, but I believe the thermometers read close to 100F at the time.

gmaslov• 14 years ago

Of course, in "hot" data centers today the environment is no more dangerous than a nice sauna, but this development makes me imagine what it might progress to in 10 or 20 years. This is the first small step across that threshold between "comfortable for humans" and "comfortable for machines" in data centers, and the first such step is usually the hardest one. If it's more efficient to run the servers in an even hotter environment, or in one that's less-habitable in some other way, you can probably expect it to happen, now that the baseline technology and ideas are here.

Not that I'm trying to seriously forecast anything, or have any special knowledge of data center design; this is just a pleasant exercise in near-future sci-fi.

cd347• 14 years ago

Years ago a data center outside DC in Silicon Alley had an A/C failure. Our equipment was reporting temps of 140F on intake. We were allowed 10 minutes in, one person doing work, another observer, both required to have squirt water bottles and a two-way radio. We were instructed not to carry anything and to use a cart. We were told not to remove equipment that weighed more than a few pounds.

I pulled 10 drives so we could run them to another data center as a 'just in case'. The guy I was with passed out about 60' from the door. The air temp outside was ~72F and they had portable hurricane fans blowing air into the data center.

In that ten minutes, I drank 32 ounces of water. I remember that because I went to pick him up, kicked my water bottle by accident and it fell over because it was empty.

He spent 30 minutes in an ambulance, about three hours in a hospital from 10 minutes exposure. It took me about two hours to recover to the point where I felt I could eat.

Don't lose respect for heat. :)

nakkiel• 14 years ago

I used to work at the CSTJF in Pau, France which is one of Total's biggest cluster (if not the biggest). Their data-center was ranked 91 in the top-100 at the time.

In the event of a fire, they have (had?) a system that would release a gaz in the data-center that would "eat" oxygen so that the said fire would die.

Obviously any living creatures trapped in the data-center would die as well. The evacuation time before release was perhaps something like 30 to 60 seconds (I can't remember that). Just enough to drop anything and reach one of the safe corridor where no gaz is released.

cd347• 14 years ago

Halon 1301 is the gas that used to be used which was banned in the 90s. Most inert gas fire suppression systems use HFCs or Ketones now and have a ten minute hold time. They work by displacing the oxygen and reducing it to <10% which is not enough to support flame - or life.

In '86, I was in a data center that had expanded to take up 70% more space. During the expansion, emergency lighting hadn't been put up. During expansion, a 470 volt three-phase line had been put in, the insulation had been stripped off while they were pulling it through the conduit. As it heated up, gas or vapors from the melted insulation built up and the 1/4" thick conduit was ripped open with roughly an 8" hole and an explosion people on the first floor heard (computer room was in the basement).

One of the operators panicked, tripped over the anti static carpet, ripped the Fire Suppression box off the wall and pulled the Halon. He stumbled out the automatic sliding glass doors and hit the EPO leaving the data center completely dark with me about 120' from the door in pitch black.

I had walked those corridors between the drives hundreds of times, but, had difficulty finding the path. Time was running out, so, I stood on one of the minicomputers, moved one of the drop ceiling tiles and stuck my head into the return air plenum and the Halon went off. It was noisy, sort of a giant whoosh with a low rumble and a very odd smell.

I don't know how long I stood there, but, it wasn't more than a few minutes before a flashlight was shining on me with a Fireman in full gear.

After that, we had emergency lighting and oxygen tanks throughout and the Halon system was upgraded. When the tanks were refilled, they did the math and noticed that the amount of Halon we had wasn't enough for the expanded data center and probably wouldn't have extinguished a fire.

Most humorous moment - seeing firemen walk through the data center with axes in hand looking for fire.

amalag• 14 years ago

I wonder how much money companies waste by keeping their server rooms as cold as a refrigerator. Some IT guy who thinks servers should be cold probably told them that.

Zaak• 14 years ago

For a long time it was common knowledge that computers last longer if you keep them cold. It's only been in the past few years that evidence has been shown that moderately high temperatures do not appreciably shorten equipment life.

jordanb• 14 years ago

It's also conceivable to me that it used to be more true in the past than it is now. Computer equipment used to be incredibly fragile.

twelvechairs2• 14 years ago

This is a very interesting case. As an architect though I can't help putting in my 2 cents that cooling isn't simply a binary choice.

Firstly, the best thing to do environmentally would be to use the heat positively, connecting it into a centralised heat-distribution network for other users (for instance, other industries, public heated pools, or even residences).

Secondly, even without power, there is a lot you can do to maximise the heat-loss of a building: Eg. design to capture prevailing winds and utilise them to help heat escape, or internal arrangements to keep cooler 'microclimates' around areas used by maintenance staff and temperature-critical server elements. I am not sure what the design process of these buildings is, but I would bet that this sort of design doesn't get thought about.

Thirdly, you can also actively cool buildings without 'chillers' (refrigeration units), such as pumping earth-cooled water through the building (as 'chilled beams'). This is actually likely to be quite cost-effective for large projects like this, and much more environmentally friendly than burning coal.

cd347• 14 years ago

Facebook's Prineville datacenter is aligned to capture prevailing winds:

http://www.facebook.com/prinevilleDataCenter

Somewhere I had whitepapers from the Open Data Center Initiative which did touch on some of the issues you mentioned. http://www.opendatacenteralliance.org/ is the alliance page, but, requires membership, has a few whitepapers and webcasts available.

Drbble• 14 years ago

Why would you bet that professionals with huge budgets candidate cost-conscious customers wouldn't think about how to solve the problem they're paid to solve? If they don't, you could be a billionaire by selling your ideas.

twelvechairs2• 14 years ago

I think the big clients (google, facebook, et. al) are getting smarter very quickly now (see for instance cd34's link above). It also requires not just one person, but a whole team of smart architects, engineers and environmental experts to figure this out for every individual server centre.

Also - some of the big successes (heat sharing, using water from outside sources, etc.) also require government involvement, which can be a minefield in itself (note: google seems to have much better success with these government schemes in Europe than in the USA).

antonyme2• 14 years ago

One aspect of this approach they don't mention is how it affects the MTBF of the equipment. Many components suffer increased failure rates when run at a consistently higher temperature. While it may be relatively safe to run machines in a range higher than is comfortable for humans, I bet there's an upper limit past which components really start to fail in numbers.

tikhonj• 14 years ago

The article mentions that "Studies by Intel and Microsoft showed that most servers do fine with higher temperatures and outside air, easing fears about higher hardware failure rates." So I think it isn't a big issue. Now, obviously there is going to be some upper limit, but it just hasn't been hit in this case.

mvgoogler• 14 years ago

We've published a few papers about this that studied (among other things) the effect of temperature on DRAM and hard-drive failure rates. We watch our machines pretty closely. If you're a data geek, Google's a fun place to be.

Disk Study: http://research.google.com/archive/disk_failures.pdf

DRAM Study: http://www.cs.toronto.edu/~bianca/papers/sigmetrics09.pdf

antonyme2• 14 years ago

Very interesting! Thanks for the links, I'll check out the papers.

ajasmin• 14 years ago

If it gets too hot for humans can't we use robots instead?

justincormack2• 14 years ago

The other option is not to fix stuff, just leave failed stuff in place. Various people have done this, all depends on costs.

abalashov• 14 years ago

Hope that mindset does not come to pervade the nuclear power industry. :-)

Smudge• 14 years ago

Did anyone read the last two paragraphs? Seems the article wasn't quite done being edited:

> Before entering the hot aisle, a technician uses a supply trigger, typically a switch located outside the hot aisle, to activate the SmartAire T units. Cool air then enters the hot aisle until a comfortable temperature is established. SmartAire T units maintain this temperature until the technician completes the assigned work and deactivates the units, eliminating any need for rest periods and increasing productivity.

> Before entering the hot aisle, a technician can use a supply trigger – typically a switch located outside the hot aisle – to activate the SmartAire T units. Cool air then enters the hot aisle until the temperature reaches a comfortable level.

DanielBMarkham• 14 years ago

Is it just me, or did this article strike a dystopian tone? Computer centers of the future, perhaps achieving truly useful AI capabilities, consisting of unimaginable numbers of racks sweltering in a heat so hot that people can't survive in the same room with them? Sounds like something Dante would have written if he were alive in 2012.

karamazov• 14 years ago

I don't think so - to me, the tone seems informative: "hey, did you know that data centers might not need all that cooling? here's an example."

Plus, humans can work for about 80-90 minutes at close to 100 F (albeit not comfortably)[1], so we're not really talking about conditions that would kill people. One can extrapolate, of course, but it's quite possible that the servers would break down before the humans do.

[1] http://www.ncbi.nlm.nih.gov/pubmed/9183079

nullflux2• 14 years ago

We also seem to get along fine in space, under water, in low oxygen environments, in irradiated environments, in freezing environments...

The point of this is: who cares if the data center is warm/hot? It's as hot as that inside a mascot suit at a theme park, so they build cooling mechanisms into them. Tools exist for a reason, and it is somewhat ironic that we prematurely assume that our creations require the same environment for "comfortable" survival that we do. The animistic tendencies we have may not just be cultural.

PaulHoule• 14 years ago

These guys are whimps.

I used to work in an academic building with an ancient HVAC system in which temperatures in my office would soar to 105 degrees in April, between having no AC, sun shining in the big windows, plus the heat dissipation from 5 humans and 20 computers. My deck included a Dell Windows machine and two old IBM machines running Linux and a Linux laptop and a Sun Ultra 10 and a "Pizza Box" 32-bit SPARC machine and two Sun Rays.

(Even if they couldn't charge enough tuition to get a decent A/C system, at least I had access to a pool of last year's hardware.)

We never evacuated... You see, that's why the U.S. is #1 -- people in any other country would bail out at 95, but we stay the course. ;-)

DanBC2• 14 years ago

I'm interested in how much "efficiency" can be built in to new data centres.

Is it possible to use the waste heat for other purposes? Would painting the roof white make any difference?

mjwalshe• 14 years ago

at one of BT's Datacetres one hot summer we played water hoses on the roof to increase cooling via evaporation

tripzilch• 14 years ago

> During these periods, the temperature inside the data center can rise above 95 degrees.

:-/ 95 degrees what? They don't use Fahrenheit in Belgium, you know (nor does most of the rest of the world, for that matter).

For anyone wondering, 95F is exactly 35 degrees Celsius.

Also, it would probably have been more relevant to mention the equivalent Belgian and EU institutes instead of the OSHA ... seriously, I don't expect for a second that the regulations would be the same. Roughly, maybe, but it just doesn't make sense to mention the OSHA at all if the servers aren't in the USA!

sneak• 14 years ago

As someone who spent his first pair of decades in the USA, it's easy to forget that most Americans view the whole world as if it were the USA. It's a habit that seems normal in that environment.

They also frequently say "the world" when they mean "the whole country".

jballanc• 14 years ago

I honestly have to wonder why we don't have robots doing the majority of these tasks. Obviously, a robot couldn't troubleshoot detailed or obscure problems, but for things like provisioning a server, rerouting around bad network hardware, replacing drives, NICs, etc. they should be good enough. CERN already uses robots for the LHC tape backup system. I can't see that this would be that much more complicated.

adpowers• 14 years ago

Humans are very easy to train compared to robots, and aren't that expensive. I'd imagine each facility is laid out slightly differently, with different generations of hardware. To make the robot work well you'd either have to program in each hardware variation or make the software sufficiently advanced to understand the differences itself and adapt. I imagine the cost/benefit wouldn't pan out when you look at how many datacenter techs you replace with how many software and hardware engineers.

Humans are great at adapting, so if you throw a new enclosure at them or a new motherboard design which has the CPU sockets in a different location, they'll be able to learn the new system in 30 minutes.

A former coworker of mine trained to work with factory robots, but he realized that there wasn't much of a current job market for it because humans are still way cheaper (and will be for some time). Instead he went into software.

awongh• 14 years ago

I can't help but think about the logical extreme of this type of trend, which is to put the server rack itself outside- what components would you need to weather seal or protect against the elements? There are fans and disks that have moving parts, and cable connections you would have to seal, but other than those changes what would you have to do? Maybe it would be even more efficient....

Too Hot for Humans, But Google Servers Keep Humming

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