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Google Calls For Power Supply Design Changes
Raindance writes "The New York Times reports that Google is calling 'for a shift from multivoltage power supplies to a single 12-volt standard. Although voltage conversion would still take place on the PC motherboard, the simpler design of the new power supply would make it easier to achieve higher overall efficiencies ... The Google white paper argues that the opportunity for power savings is immense — by deploying the new power supplies in 100 million desktop PC's running eight hours a day, it will be possible to save 40 billion kilowatt-hours over three years, or more than $5 billion at California's energy rates.' This may have something to do with the electricity bill for Google's estimated 450,000 servers."
google hires experts on Electrical Engineering to figure out how to reduce the power bill on those 450,000 servers. Hell, I'm all for it. Less power means less heat means quieter fans (w/o spending an arm/leg on an Antec Sonata or whathaveyou).
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In the old days, disk drive motors and fans. But many of these now run on 5V, hence the cheap USB-powered drive cases out there. Chips at CMOS power levels run at 3.3v, TTL is 5v, but hardly anything runs at 12v anymore. It seems to me that if they'd just pick their hardware carfully, they could run their entire server rack off of 5v+- rails.
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I would bet a lot of the employees at Google have Electrical Engineering degrees. Don't underestimate the brain power Google has in its employee base. But the power supply issue they're trying to address isn't a technical challenge, but a political challenge.
You can say goodbye to USB powered devices. An example would be the canned drink cooler.
Thanks,
Jim
The ability to have all my machines powered by a heavy cable carrying 12VDC would be pretty useful for several reasons.
*sigh*
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n/m found it.
t e_paper.pdf
http://services.google.com/blog_resources/PSU_whi
I have been saying this for years. We lose 10-20 % of energy charging a battery in a UPS with 117V, we lose another 20-30% in the inverter to get it back to 117V, and then we lose another 10% getting the 117V back to usable voltages for the PC.
It does not take an expert in electrical engineering, just common sense.
Can I sue google for stealing my idea?
A lot of telco equipment is designed to run on -48 volts DC and PC and server power supplies are readily available at this voltage.
The advantage of -48 over 12 volts is that there will be less loss through resistance and smaller conductors can be used. Of course, there is a greater risk of electric shock, but I would think -48 would be pretty safe.
48 volts is also the standard for Power over Ethernet (IEEE 802.3af). This may not be compatible, though, since telcos run -48, not +48, though some equipment can operate with either (though some cannot).
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Most of the postings so far have it all wrong. Google is not proposing 12VDC into a desktop PC or 12VDC distribution within the data center. What they're proposing is that the only DC voltage distributed around a computer case should be 12VDC. Any other voltages needed would be converted on the board that needed it.
This is called "point of load conversion", and involves small switching regulators near each load. Here's a tutorial on point of load power conversion.
It's been a long time since CPUs ran directly from the +5 supply. There's already point of load conversion on the motherboard near the CPU. Google just wants to make that work off the +12 supply, and get rid of the current +5/-5/+12/-12 output set.
The Mac Mini will boot and run on a 12-volt supply. It only takes 17v so that it can provide Firewire power.
-jcr
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Serial remains one of the most manageable approaches to console management. Video is, obviously, not loggable, not automatically monitorable, not greppable, and not amenable to low throughput, high latency remote access.. Serial devices and consequently drivers for them are so simple and straightforward, and the behavior so deterministic, that it is far preferable to something more complex (ethernet and usb) for a console. Ethernet certainly in questionable circumstances may suggest a driver unload/reload as a step to problem resolution, which is safer if not using as a console (though many times I have used ssh and chained the commands using semicolons). For example in that case, if your path contains an nfs mount, and you forget about it as you yank the network out, your chained command will hang as the shell tries to stat the nfs mount for the path. Part of the problem with relying solely upon the ethernet for console is the ethernet has more than one job to do, so it takes a fair amount more competent engineering to get to work right. Many newer systems offer to redirect textual serial traffic over IPMI, and that is admittedly decent *if* the vendor architects it robustly, which is difficult to ensure beyond hands-on experience with a brand and trusting in their consistancy. For example, e326 servers from IBM I wouldn't trust the net console, but an IBM x3455 I would be more confident in. USB, again, has similar complexity issues (it's multiplexed for keyboard/mouse/mass/storage/printing/scanning/etc etc). If you theoretically had bi-directional text console over some usb device, it's more difficult for a low level, simple piece of software to set up the usb controller and all requisite activities, then traverse the bus, identify the console devices, and then use it. Just like with an ethernet device where you may have cause to unload and reload a driver, a usb controller out to lunch with respect to a mass storage device would cause a similar issue. Enterprise distribution kernels tend to compile in the serial console and leave the usb controller modular, specifically with serial consoles in mind.
Serial console servers, in answer to your question, provide a scalable way for systems to access via the network serial consoles. By being dedicated, moderately simple systems with 40+ serial cables, they can provide access (via telnet generally) to a rack's worth of 1U servers, automatically log the content, or at the very least provide an administrator with remote console access at will to any given system.
Serial console is not obsolete in the least bit, just because it can't run your '31337' aero interface, or whatever nice and shiny interface that makes poser administrators and PHBs drool, doesn't mean good, serious systems administrators don't consider the technology to be a vital part of a robust management strategy.
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There are different kinds of UPSes that do this in different ways. The two major types used for PCs are called "line interactive offline" and "dual conversion online". The first just passes the AC power straight through to the output. If the AC power coming in goes out of range, then it flips a switch internally (relay, contactor, thyristor, etc) to supply the power from an inverter driven by the battery. The second converts the AC coming in to DC all the time, and converts that DC back to AC for output. It then does the switching in DC, or parallels the DC with the battery directly. These variations are classified as "topology" by many manufacturers.
Both of these kinds can have inverters that produce square waves, pseudo-sine waves, or very nice clean sine waves. The dual conversion type can also isolate a poor power factor (the deviation of the current wavefrom from being a sine wave in sync with the voltage) of the PC power supply from the power source. A poor power factor means the product of the average current times the average voltage (apparent power) exceeds the actual real power (average of all the products of the voltage and current and each point in time) being used, which results in reduced efficiency and other problems.
now we need to go OSS in diesel cars