That idea is a non-starter. Consider the cost of transportation, the cost of connecting all those ridiculously slow CPUs and incompatible CPUs together, powering them, programming for them. Building a supercomputer using standard x86_64 CPUs will probably be cheaper.
Here's an example: http://www.androidauthority.com/samsung-galaxy-s3-sales-20-m... Within a few years there will be 20 million Samsung Galaxy S III's with dead batteries and/or cracked screens. That's a dual-core 1 GHz ARM with 1 GB of RAM, 8 GB of SSD, and a hardware GPU.
Right now, there are professional 1st-world developers developing apps for all those "incompatible CPUs". So it's possible and even cost effective under the right circumstances.
Yet someone is currently being paid to haul away this stuff as electronic recycling.
Xeon just blows the ARM chip out of the water in Performance per Watt used. A modern day Xeon gives you somewhere on the order of 20x more performance per watt compared to a Snapdragon S4 Pro. Otherwise, all the electricity that it takes to run your supercomputer built out of crap chips will make your supercomputer more costly to run in the long term.
I don't know, but the Snapdragon has 1MB of Cache, while the Xeon has 20MB of Cache. Furthermore, the Xeon actually has a multi-socket connector... so two Xeons can talk to each other at a rate of 25.6 GB/s through QPI (QuickPath Interconnect).
So my bet on memory is that Xeon wins that too.
On the multi-processor communications issue... I doubt that the Snapdragon would have PCIe connections... let alone a high-bandwidth low-latency connection like the Xeon's QPI.
There's a reason why supercomputers stick with Intel or AMD. They've got the processor power, the performance per watts, and I/O girth to communicate to other processors. A small embedded chip (like Snapdragon), just doesn't have the features to make a supercomputer out of.
ARM does have promise though, its just not in Snapdragons. As noted, the primary issue in Supercomputers is bandwidth (so that the processors can talk to each other).
Calxeda for example has spent a lot of time trying to solve this interconnect issue. Each Calxeda card is composed of 4 CPUs. Every CPU has 8 10Gb (aka: 1GB) ethernet links, 2 8xPCI connections and more.
Its a relatively young project, but they're moving towards the right direction. There are rumors that Facebook is deploying a Calxeda server.
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That idea is a non-starter. Consider the cost of transportation, the cost of connecting all those ridiculously slow CPUs and incompatible CPUs together, powering them, programming for them. Building a supercomputer using standard x86_64 CPUs will probably be cheaper.
Here's an example: http://www.androidauthority.com/samsung-galaxy-s3-sales-20-m... Within a few years there will be 20 million Samsung Galaxy S III's with dead batteries and/or cracked screens. That's a dual-core 1 GHz ARM with 1 GB of RAM, 8 GB of SSD, and a hardware GPU.
Right now, there are professional 1st-world developers developing apps for all those "incompatible CPUs". So it's possible and even cost effective under the right circumstances.
Yet someone is currently being paid to haul away this stuff as electronic recycling.
A great example of why Xeons are superior. :-)
Snapdragon S4 completes the Linpack benchmark with 460 MegaFlops: http://www.androidauthority.com/snapdragon-s4-pro-vs-exynos-.... Snapdragon is rumored to use ~3 to 5 Watts of power.
Consider a Xeon E5-2690: which gets you 347,000 MegaFlops of performance in 135 Watts. http://www.intel.com/content/www/us/en/benchmarks/server/xeo...
Xeon just blows the ARM chip out of the water in Performance per Watt used. A modern day Xeon gives you somewhere on the order of 20x more performance per watt compared to a Snapdragon S4 Pro. Otherwise, all the electricity that it takes to run your supercomputer built out of crap chips will make your supercomputer more costly to run in the long term.
Does Linpack even touch the memory bus?
I don't know, but the Snapdragon has 1MB of Cache, while the Xeon has 20MB of Cache. Furthermore, the Xeon actually has a multi-socket connector... so two Xeons can talk to each other at a rate of 25.6 GB/s through QPI (QuickPath Interconnect).
So my bet on memory is that Xeon wins that too.
On the multi-processor communications issue... I doubt that the Snapdragon would have PCIe connections... let alone a high-bandwidth low-latency connection like the Xeon's QPI.
There's a reason why supercomputers stick with Intel or AMD. They've got the processor power, the performance per watts, and I/O girth to communicate to other processors. A small embedded chip (like Snapdragon), just doesn't have the features to make a supercomputer out of.
OK, I'm sold.
ARM does have promise though, its just not in Snapdragons. As noted, the primary issue in Supercomputers is bandwidth (so that the processors can talk to each other).
Calxeda for example has spent a lot of time trying to solve this interconnect issue. Each Calxeda card is composed of 4 CPUs. Every CPU has 8 10Gb (aka: 1GB) ethernet links, 2 8xPCI connections and more.
Its a relatively young project, but they're moving towards the right direction. There are rumors that Facebook is deploying a Calxeda server.