Investigating Cavium's ThunderX: The First ARM Server SoC With Ambition
by Johan De Gelas on June 15, 2016 8:00 AM EST- Posted in
- SoCs
- IT Computing
- Enterprise
- Enterprise CPUs
- Microserver
- Cavium
Comparing With the Other ARMs
We did not have access to any recent Cortex-A57 or X-Gene platform to run the full SPEC CPU2006 suite. But we can still combine our previous findings with those that have been published on the 7-cpu.com. The first X-Gene 1 result is our own measurement, the second one is the best we could find.
| SKU | Clock | Baseline Xeon D Compress | Baseline Xeon D Decompress |
| Atom C2720 | 2.4 | 1687 | 2114 |
| X-Gene 1 (AT bench) | 2.4 | 1580 | 1864 |
| X-Gene 1 (best) | 2.4 | 1770 | 1980 |
| Cortex-A57 | 1.9 | 1500 | 2330 |
| ThunderX | 2.0 | 1547 | 2042 |
| Xeon D1557 | 1.5-2.1 | 3079 | 2320 |
| Xeon E5-2640 v4 | 2.4-2.6 | 3755 | 2943 |
| Xeon E5-2690 v3 | 2.6-3.5 | 4599 | 3811 |
Let's translate this to percentages, where we compare the Thunder-X performance to the Xeon D and the Cortex-A57, two architectures it must try to beat. The first one is to open a broader market, the second one to justify the development of a homegrown ARMv8 microarchitecture.
| SKU | Clock | Baseline Xeon D Compress | Baseline Xeon D Decompress | Baseline A57 Compress | Baseline A57 Decompress |
| Atom C2720 | 2.4 | 55% | 91% | 112% | 91% |
| X-Gene (AT bench) | 2.4 | 51% | 80% | 105% | 80% |
| X-Gene (best) | 2.4 | 57% | 85% | 118% | 85% |
| Cortex-A57 | 1.9 | 49% | 100% | 100% | 100% |
| ThunderX | 2.0 | 50% | 88% | 103% | 88% |
| Xeon D1557 | 2.1 | 100% | 100% | 205% | 100% |
| Xeon E5-2640 v4 | 2.4 | 122% | 127% | 250% | 126% |
| Xeon E5-2690 v3 | 3.5 | 149% | 164% | 307% | 164% |
First of all, these benchmarks should be placed in perspective: they tend to have a different profile than most server applications. For example compression relies a lot on memory latency and TLB efficiency. Decompression relies on integer instructions (shift, multiply). Since this test has unpredictable branches, the ThunderX has an advantage.
The ThunderX at 2 GHz performs more or less like an A57 core at the same speed. Considering that AMD only got eight A57 cores inside a power envelope of 32W using similar process technology, you could imagine that a A57 chip would be able to fit 32 cores at the most in a 120W TDP envelope. So Cavium did quite well fitting about 50% more cores inside the same power envelope using an old 28 nm high-k metal gate process.
Nevertheless, a 120W Xeon E5 offers about 2.5-3 times higher compression performance. The gap is indeed much smaller in decompression, where the wide Broadwell core is only 13% (!) faster than the narrow ThunderX core (compare the Xeon D-1557 with the ThunderX).
Facebook
Twitter
RSS
82 Comments
View All Comments
silverblue - Thursday, June 16, 2016 - link
I'm not sure how this is relevant. Johan doesn't review graphics cards, other people at Anandtech do. I bet Guru3D has a much bigger team for that, and I imagine that they have a much narrower scope (i.e. no server stuff).I don't think I've looked at a review recently that hasn't had the comments section polluted with "where is the review for x".
UrQuan3 - Wednesday, June 15, 2016 - link
Intel allows their Xeons to sometimes pull double their TDP? No wonder our new machines trip breakers long before I thought they would. I need to test instead of assuming accurate documentation.I can see why you chose C-Ray, I'm just sorry a more general ray tracer was not chosen. Still, not it's intended market, though I am suddenly very interested. Ray-tracing and video encoding are my top two tasks.
Meteor2 - Thursday, June 16, 2016 - link
The 'T' in 'TDP' is for thermal. It's a measure of the maximum waste heat which needs to be removed over a certain period of time.UrQuan3 - Wednesday, June 22, 2016 - link
Yes, it stands for thermal, but power doesn't consumed doesn't just disappear. Convert it to light, convert it to motion, convert it to heat, etc. In this case there is a small amount of motion (electrons) and the rest has to be heat. I expect much higher instantaneous pulls, but this was sustained power. Anyway, I will track down the AVX documentation mentioned below.I saw the h264ref. I'll be curious about x264 (handbrake) as the authors seem interested in ARM in the last few years. Unsurprisingly, it is far less optimized than x64. I benchmarked handbrake on the Pi2, Pandaboard, and CI-20 last year, just to see what it would do.
JohanAnandtech - Thursday, June 16, 2016 - link
C-Ray was just a place holder to measure FPU energy consumption. I look into bringing a more potent raytracer into our benchmark suite (povray)Video encoding was in the review though, somewhat (h264ref).
patrickjp93 - Friday, June 17, 2016 - link
ARM chips with vector extensions allow it as well. Intel provides separate documentation for AVX-workload TDPs.Antony Newman - Wednesday, June 15, 2016 - link
Fascinating article.Why would Cavium not try and use 54 x A73s in their next chip?
If ARM are not in the business of making Silicon, and ARM think the '1.2W Ares' will help them break into the Server market ... Then Why do we think ARM isn't working with the likes of Cavium to get a Server SoC that rocks the Intel boat?
Typos From memory : send -> sent. Through-> thought. There were a few others.
AJ
name99 - Thursday, June 16, 2016 - link
How do you know ARM aren't working with such a vendor?ARM has always said that they expect ARM server CPUs to only be marginally competitive (for very limited situations) in 2017, and to only be really competitive in 2020.
That suggests, among other things, that if they are working with partners, they have a target launch between those two dates, and they regard all launches before 2017 as essentially nice for PR and fr building up the ecosystem, but essentially irrelevant for commercial purposes.
rahvin - Thursday, June 16, 2016 - link
The problem as pointed out early in this article is that ARM keeps targeting Intel's current products, not the ones that will be out when they get their products out. We've had almost a dozen vendors get to the point of releasing the chip and drop it because it is simply not competitive with Intel. Most of these arm products were under taken when Intel was targeting performance without regard to performance/watt. Now that intel targets the later metric arm server chips haven't been competitive with them.Fact is Intel could decimate and totally take over all the markets arm chips occupy, but to do it they'd have to cannibalize their existing high profit sales. This is why they keep canceling Atom chips, the chips turned out so good they were worried they'd cannibalize much more expensive products. This is the reason Avoton is highly restricted in what products and price segments it's allowed into. If Intel opened the flood gates on Avoton they would risk cannibalizing their own server profits.
junky77 - Wednesday, June 15, 2016 - link
So, they did what AMD couldn't for years? I'm trying to figure it out.. their offering seems to be a lot more interesting than AMD's stuff currently