Slashdot Mirror
12-Core ARM Cluster Beats Intel Atom, AMD Fusion
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.
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.
Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
half the fun is building it. good excuse to build a 12-core mini-cluster. I think this is nothing more than some nerd showing off his latest toy. Which is not a bad thing. this 12-core'd cluster might be useful, at the very least proof of concept stage. I could imagine the uses for a highly paralleled mini-super-computer on an affordable budget.
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.
"Besides winning on performance and efficiency, the Core i7 3770K system would cost less than the cost of a six PandaBoard ES cluster setup."
So a single Ivy Bridge system, which takes up much less rack space, no cluster network ports, outperforms and costs less than the ARM cluster. Is that the definition of a no-brainer?
I think the confusion is that people think Atom is analog to ARM. People keep confusing the fact that ARM is a core processor and Atom an SoC solution. It makes no sense comparing apples to oranges. An appropriate comparison would be an SoC from TI, Qualcomm or Samsung.
With the EP.C workload on all twelve ARM cores, the average power consumption was 30.4 Watts for all six PandaBoards, which is in line with each PandaBoard burning through 5~6 Watts under load. When it comes to the performance-per-Watt, the EP.C test was yielding an average of 1.78 Mop/s per Watt, which was an increase over the single PandaBoard ES at 1.60 Mop/s per Watt.
Page 8 of TFA (yes, my quote was the entire text on that page) claims otherwise, that efficiency of the cluster is even better than that of a single board. I really have no idea how they managed that.
PlusFive Slashdot reader for Android. Can post comments.
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.
AntiFA: An abbreviation for Anti First Amendment.
Ivy bridge is more efficent in work done per watt yes, but ARM still wins for low power devices like phones because it draws so much less power. The fact that it does less with that power is moot, because it does enough and lets your battery last much longqer.
Silence is a state of mime.
I think the confusion is that people think Atom is analog to ARM. People keep confusing the fact that ARM is a core processor and Atom an SoC solution. It makes no sense comparing apples to oranges. An appropriate comparison would be an SoC from TI, Qualcomm or Samsung.
But then how could they generate media hype by announcing they are outperforming intel?