> <i>In a typical UPS backup scenario in a normal datacenter, the incoming power is converted from AC to DC so the battery can be charged, then converted back to AC coming out of the battery to be distributed out to the power distribution units, where it is stepped down to the 120 volts where the servers consume it. By putting the batteries in the servers, Microsoft can do one AC to DC conversion and distribute 380 volts DC directly to the Open Cloud Server power supplies and then step it down to 12 volts for the server and storage nodes.</i><p>This is a huge point of efficiency that's been missed for a very long time, mostly because it's right along the border between the datacenter provider and the server customer. The datacenter traditionally agrees to provide filtered 120/240v AC.<p>Converting the power loses efficiency. And we convert the power 4 times. They may be regaining about a 6.25% loss from each conversion, my math is probably incorrect.<p>Of course, all parties could agree to change the standard, and provide clean, filtered 12V DC to servers, and redesign PSUs to accept this input instead. But then they wouldn't be wall-pluggable anymore.
I remember reading about Google doing this years ago. I've been disappointed ever since that Dell et al haven't adopted a similar option for their commodity hardware.
Slightly off-topic: in one gig we are running buildfarm and CI on dozens of cheap notebooks (mostly ACER and Lenovo).
And enjoying this effect of local power backup, which is very useful in our office building, because power is very unstable. When power goes down usual rack-mounted server might work tens of minutes off a UPS supply while these little bastards work for a couple of hours more, just slightly slower.
video <a href="http://youtu.be/31dwMAg-Hx4?t=330" rel="nofollow">http://youtu.be/31dwMAg-Hx4?t=330</a><p>slides <a href="http://www.opencompute.org/assets/OCP-Summit-V-Slides/Mainstage/OCP-MSFT-Kushagra.pdf" rel="nofollow">http://www.opencompute.org/assets/OCP-Summit-V-Slides/Mainst...</a><p>specs <a href="http://www.opencompute.org/wiki/Server/SpecsAndDesigns#Specifications_heading_to_the_IC" rel="nofollow">http://www.opencompute.org/wiki/Server/SpecsAndDesigns#Speci...</a><p><i>The LES shall provide sufficient ride through capacity to maintain proper PSU output for 35 seconds (+/- 500ms) minimum plus walk-in period of no less than 10 seconds (+/- 500ms). The power supply shall meet the reliability and operating life with drop outs at a maximum power of 1600W for 5 seconds then reducing to 1425W for the remainder of the drop out.
The power supply shall be capable of operating at greater than 1425W to 1600W continuous drop out but reliability and operating life of the battery are not guaranteed.</i>
3 questions:
1. What's the lifetime of an individual battery?
2. Are the batteries replaceable?
3. Will we ever see this tech in consumer level PC power supplies? If we did, would it be of any use in an environment without backup generators?
I do not understand the new dupe detection system. The same user posted the same link 10 hours ago: <a href="https://news.ycombinator.com/item?id=10368978" rel="nofollow">https://news.ycombinator.com/item?id=10368978</a>