12-Core ARM Cluster Beats Intel Atom, AMD Fusion 105
An anonymous reader writes "Phoronix constructed a low-cost, low-power 12-core ARM cluster running Ubuntu 12.04 LTS and made out of six PandaBoard ES OMAP4460 dual-core ARMv7 Cortex A9 chips. Their results show the ARM hardware is able to outperform Intel Atom and AMD Fusion processors in performance-per-Watt, except it sharply loses out to the latest-generation Intel Ivy Bridge processors." This cluster offers a commendable re-use of kitchenware. Also, this is a good opportunity to recommend your favorite de-bursting tools for articles spread over too many pages.
Re:Were they bored? (Score:5, Informative)
What would calculating the theoretical peak tell them about the (real) sustained performance?
Partitioning the problem in chunks that can be distributed to the nodes in the cluster adds overhead. Assembling the finished results does the same. It is kind of hard to predict what this over will be as it depends on the interconnect. In this case they used 100Mb/s ethernet, but there was contention from running NFS over the same network. Building it and measuring it is the only way to find out what kind of performance you really get.
Re:Were they bored? (Score:5, Informative)
What I don't understand is why the summary is focused on ARM beating Atom when the overall winner - in performance, in performance per watt, and in cost - was the Intel Ivy Bridge... by a huge margin.
SPIN (Score:4, Informative)
I'm getting Dramamine for everyone on Slashdot to counteract the ARM FUD.
1. Look at both the AMD and Intel boards for the low-end processors... notice anything? They have all of these... features like PCIe, real memory interfaces, SATA controllers, etc. etc. All of these features consume power. Huge amounts? Not really, but compared to both the E-350 and the Atom CPUs, the amount of power being measured for each board is including a very large amount of power that has zero to do with the CPU. Guess what would happen if I took an E-350 or Atom and put it in an equivalent to the Panda board?
2. Apparently ARM's marketing department ran out of money to pay the poster to describe the Ivy Bridge system used in this test. Here's the short results:
a. In the parallel benchmarks used in this test that are a (probably unrealistically) best-case scenario for the ARM cluster, a single Ivy Bridge CPU was 5 times faster.
b. Oh but ARM says: So what if Ivy is faster! It's a power hog... look it used over 100 WATTS OMG!!!! Well guess what? On a performace per-watt scale, the Ivy Bridge system is THREE TIMES BETTER THAN ARM.
c. Oh but the ARM fanboys will say that Intel cheated by using a better lithographic process!! Well guess what: ARM loudly brags that it is better because it is an IP only company, so you have to take the good with the bad.
4. Oh one more thing... the Ivy Bridge system had REAL PERIPHERALS like real memory, reali PCIe, a real SSD, etc. etc. that by themselves probably used more power than at least one of the ARM boards, probably 2 of them. Oh and by the way.. the power used for the network fabric needed to network those ARM boards... *NOT* included in the power consumption figures so ARM had that as an extra advantage! So in many ways the Ivy Bridge system was intentionally disadvantaged.. and was still THREE TIMES MORE EFFICIENT ON A PER-WATT BASIS THAN ARM IN A SERIES OF BENCHMARKS THAT ARE BEST-CASE-POSSIBLE SCENARIOS FOR ARM.
5. For all of those ARM fanbois who are about to say that PCIe, real RAM interfaces, real SATA support, etc. etc. are inelegant artifacts of the stupid x86 instruction set well.. bite me. The last 5 years of ARM trolls who have literally gone down the feature list of every feature that x86 has that ARM doesn't and found a way to call the features that ARM lacks stupid and moronic (until ARM implements them years later and then claims to have come up with them first) is pissing me off.
Did you know Atom consumes 30W? (Score:4, Informative)
So I'm asking myself how 12 ARMs equal the power consumption of one Atom. So I have sit through all the page loads. The "Atom" is a complete off-the-hself "Net Top" box designed to maximize performance (spinning hard drive and high-end graphics card) with the sole constraint of being noiseless -- i.e. the Atom was chosen by the NetTop manufacturer for low heat, not for low energy consumption.
OK, then for the comparison with Ivy Bridge, I wasn't surprised. I've been salivating about the low-power versions of Ivy Bridge for several months now. But this comparison wasn't even againt that. They used the highest clock cycle highest power 3770K variant, which is rated at 77W [wikipedia.org]. There is a 45W version for a bit lower clock speed. (BTW, Intel "produces" low-power variants the same way they "produce" high-clock variants -- they test the chips after manufacturing to see which ones draw less power.)
So, basically, the comparison is completely pointless and a waste of time.