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Facebook Putting Batteries On-Board Its Servers
1sockchuck writes "The data center of the future may have no central UPS units, and be filled with servers with on-board batteries. Facebook says it will adopt a new power distribution design that shifts the UPS and battery backup functions from the data center into the cabinet by adding a 12-volt battery to each server power supply, an approach pioneered by Google. Facebook says the move will slash its power bill and save millions in capital expenses on UPS systems and PDUs. Facebook acknowledged that these types of custom designs are limited to large companies, but called on server vendors and data center builders to adapt their offerings to make them available to smaller companies."
From the article: "Facebook's new distribution scheme calls for 277 volt power to the servers. "We're working with power supply vendors to create a (server) power supply that will accept 277 volts on the input," said Michael."
Why 277 volts?
This right after they announced they were going public. This will definitely boost their stock price.
I think facebook has some good merit, however I am an avid anti facebook poster boy when it comes to destroying
relationships. If you thought it was easy before to hook up online and cheat on your spouse, well imagine now!!!
Girlfriend: "Hey, i got over 5000 friends online, isn't it wonderful???"
Boyfriend: "ummm...why are they all pictures of young good looking dudes wearing no shirts....?"
Girlfriend: "well that's because you can put anything on there..."
Boyfriend: "how long have you know these so called friends?"
Girlfriend: "Well not long, most are people that invited me to be their friend"
Boyfriend: "Why is this guy keep writing on your wall how hot you are....I am not sure i really like this..."
Girlfriend: "You always make such a big deal about nothing..."
Since when is 12 Volts a measure of battery life? You still need to know how many Amp-Hours the battery can provide and the power usage of the server.
You could have a 100Amp-Hour 12 volt battery, or a 1Amp-Hour 12 volt battery...
What would the world be like if facebook went offline... I'm not sure I could continue living.
Only the State obtains its revenue by coercion. - Murray Rothbard
As a rough estimate I would say mission critical servers get changed out every 3, maybe 4 years. I would imagine any cells would need to be at least laptop battery sized to run the server for an appreciable period of time, so what is going to happen when a server gets replaced? Keep the battery? I don't think so.
The problem with mesh computing is that it doesn't save in energy costs. With a centralized UPS and power supply, improving efficiency requires that you upgrade one unit. This way, you have to upgrade a few hundred units. It's similar to why moving to electric cars is advocated despite their limited range and low performance: Because it's easier to upgrade a dozen power plants than a few hundred thousand cars, to take advantage of the latest technology.
#fuckbeta #iamslashdot #dicemustdie
This is interesting to me in a couple of ways.
The idea is that it is cheaper to have just a battery instead of a UPS. A UPS will also have to have an inverter.
Okay I can see this but they why have it at the server level?
Remove the power supply from the server and put it at the rack level? Have a big redundant power supply for each rack and batteries for each rack?
Or why not use DC for the entire data center and put the battery at the Data Center level?
Seems to me that there may be more than one way to skin this cat and each have it's pluses. If you are using a large number of low load balanced servers where having any one go down isn't a disaster then putting the battery on the server would give you a good trade off. You are probably more likely to have a single server to fail than a more centralized system would but the odds of taking down the system would be tiny.
I would love to see a study of the benefits of each type of system with the trade offs.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
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Facebook says the move will slash its power bill and save millions in capital expenses on UPS systems and PDUs.
And it'll move the complexity and unreliability to the server. The whole idea behind centralized UPS's (and by the way, you still need PDUs) is that you have reliability, serviceability, and economies of scale and efficiency. Now you have to monitor and service the batteries in thousands of pieces of equipment. And guess what happens when one of those batteries fails by getting cooked? Sulfuric acid all over the place (yes, even the "sealed" lead acid batteries can fail and leak) instead of the batteries being in, say, a battery room. God help us if they use lithium-ion, which would introduce us to a world of server fires and water damage, since a lot of datacenters are now dry-pipe to save costs. Nevermind that batteries and their associated electronics take up space, and that space has to come from somewhere.
So, now you have each server getting more expensive, more complex with both hardware and software (server now needs its own battery power management) heavier, bigger, featuring toxic materials, and now non-standard, non-commodity design which vendors will charge more for as they specialize the equipment.
I'm sure this all looks great on a powerpoint slide simplified into "if we put batteries in our servers, we can throw out our expensive UPS and save money!" This is just another hot/stupid trend; just because Google is doing it, doesn't make it brilliant. I stopped believing everything google was doing was a Best Practice around the same time gmail started going down for hours (and for some users, more than a day) at a time on a regular basis.
I tuned out of the article around the point where the guy from Facebook complains about cosmetic features interfering with airflow. Uh, guess what, bud? Dell's pretty front panel has been optional (saving you a few bucks sometimes) for years.
Please help metamoderate.
Facebook is also converting over to solid state drives. They will have relatively low power consumption per board. Putting both flash chips and a backup battery on each board makes sense.
How long is twelve volts going to keep a server running? A UPS would guarantee that you have enough time to finish transfers and close connections before shutting down into a safe mode, even give clients a warning before shutting down.
Volts are a measure of electrical potential, not capacity. You mean watt-hours, most likely.
How long is twelve volts going to keep a server running? A UPS would guarantee that you have enough time to finish transfers and close connections before shutting down into a safe mode, even give clients a warning before shutting down.
That depends on how big the UPS is. Many large-scale datacenter UPS's are only designed to ride out the time between when the power goes out and the generator is warmed up enough to take the load (tolerances are not 'right' when the engine is cold, so damage is caused, or the engine won't provide rated output.)
The argument is that in a "cloud", none of this matters- you only need to ride out a temporary power outage, or allow the machine to shut down properly so it doesn't have to be repaired software-wise. However, for the rest of us who don't live in poofy clouds and have non-cloud things like mail servers, yeah, you're right- the capacity in a server is pretty low.
Please help metamoderate.
Small personnal UPS usually gets 2 12V battery at 8AH to 12AH. In a server environment using the google way (cheap quad core), the computers are probably using under 200W (no video card) and probably around 100W avg. (no hard drives everything by lan?). a 12V 8AH battery can provide 96W for an hour, less the convertion rate, so it`s more than is required to put the generators online.
I used to work at a company that decided to install large, monolithic UPS systems after the power company hit them with a spike that took the entire system down for over a half hour. As they're a broadcasting company, they (rightly) felt that feeding their network affiliates nothing was not a good idea.
As a result, they have these UPS "rooms" that hum like the dickens when you're passing them in the hall, all with batteries that will need to be replaced regularly (just like the Google server battery systems, so it's the same problem no matter what). Reason for the hum?
The hum is caused by these giant transformers that step the power from DC to AC and create 110 volts of AC current at whatever amperage is required for normal devices. But there is a lot of wasted energy in doing that.
Computers and servers all run off of DC power. They plug into AC power and then run that AC through a "power supply" that converts that to DC that the computer can use. That takes power, but power is plentiful when it comes from the power company and you pay your bill on time. But when you take the power from the power company, then change it to DC to charge batteries and then take power from those batteries to change it to AC to power normal wall outlets only to take that through a server's power supply to change it to DC again for the computer to use it, you're looking at lots of wasted energy in just changing from AC to DC, back and then back again, as well as changing to the kind of voltage and amperage needed to run the microprocessor, power the memory and power the drive arrays.
So this is all about lowering consumption. And if you lower consumption, you lower your electricity costs.
The hobbyist magazines were all aflutter some years ago about using photovoltaic (solar) energy to power a house. But what everyone had to do (early on) was to change their appliances (or order special ones) to run on DC -- not because you couldn't make AC current from the DC output of the photovoltaic systems but because it took a lot of energy to do that and these hobbyists were all about trying to save so much energy that they could take themselves off the grid.
Here, on a large scale, you see the same idea. It's just more efficient to do this. And one of the big arguments in the early years of electrification was between DC power distribution (Thomas Edison) and AC power distribution (George Westinghouse and Nikola Tesla). We may wind up fighting these battles again in the near future.
Gods don't kill people, people with gods kill people.
Well, you need to take into account the full cost of ownership. Are those servers using 500W of power to run, doing 1/4th of the work of a new server requiring only 300W ? At 10c/kWh, it cost you 1500$ / year to keep them running not including the climatisation, beside the wasted space (4 times more than the newer servers), and you will not be able to sell them at a meaningfull value after too long.
I for one would be very interested in a standard for consumer UPSes that has them output 12v DC, and an ATX (or BTX) motherboard extension that allows it to take 12v DC in for its power needs. Failing that, a DC-DC power supply could be used.
The point being that it's dumb that a UPS has to invert the power coming out of it just so the power supply can rectify it back to DC. I'd much prefer saving the step and running DC straight from the UPS to the motherboard.
Come to think of it, the standard isn't necessary, a UPS manufacturer could do this today, although they would have to bundle the dummy power supply with the UPS. The cost could even be kept somewhat reasonable if you factor in the savings from not having to buy a power supply. The only major sticking point is that most UPS vendors put out a lot of distressingly bad products and the consumer trust issue will be a problem.
I read the internet for the articles.
Why do you assume that the in-server batteries will be completely ignored but a central UPS will be meticulously maintained?