Sizing Up Servers: Intel's Skylake-SP Xeon versus AMD's EPYC 7000 - The Server CPU Battle of the Decade?
by Johan De Gelas & Ian Cutress on July 11, 2017 12:15 PM EST- Posted in
- CPUs
- AMD
- Intel
- Xeon
- Enterprise
- Skylake
- Zen
- Naples
- Skylake-SP
- EPYC
SMT Integer Performance With SPEC CPU2006
Next, to test the performance impact of simultaneous multithreading (SMT) on a single core, we test with two threads on the same core. This way we can evaluate how well the core handles SMT.
Subtest | Application type | Xeon E5-2690 @ 3.8 | Xeon E5-2690 v3 @ 3.5 | Xeon E5-2699 v4 @ 3.6 | EPYC 7601 @3.2 | Xeon 8176 @ 3.8 |
400.perlbench | Spam filter | 39.8 | 43.9 | 47.2 | 40.6 | 55.2 |
401.bzip2 | Compression | 32.6 | 32.3 | 32.8 | 33.9 | 34.8 |
403.gcc | Compiling | 40.7 | 43.8 | 32.5 | 41.6 | 32.1 |
429.mcf | Vehicle scheduling | 44.7 | 51.3 | 55.8 | 44.2 | 56.6 |
445.gobmk | Game AI | 36.6 | 35.9 | 38.1 | 36.4 | 39.4 |
456.hmmer | Protein seq. analyses | 32.5 | 34.1 | 40.9 | 34.9 | 44.3 |
458.sjeng | Chess | 36.4 | 36.9 | 39.5 | 36 | 41.9 |
462.libquantum | Quantum sim | 75 | 73.4 | 89 | 89.2 | 91.7 |
464.h264ref | Video encoding | 52.4 | 58.2 | 58.5 | 56.1 | 75.3 |
471.omnetpp | Network sim | 25.4 | 30.4 | 48.5 | 26.6 | 42.1 |
473.astar | Pathfinding | 31.4 | 33.6 | 36.6 | 29 | 37.5 |
483.xalancbmk | XML processing | 43.7 | 53.7 | 78.2 | 37.8 | 78 |
Now on a percentage basis versus the single-threaded results, so that we can see how much performance we gained from enabling SMT:
Subtest | Application type | Xeon E5-2699 v4 @ 3.6 | EPYC 7601 @3.2 | Xeon 8176 @ 3.8 |
400.perlbench | Spam filter | 109% | 131% | 110% |
401.bzip2 | Compression | 137% | 141% | 128% |
403.gcc | Compiling | 137% | 119% | 131% |
429.mcf | Vehicle scheduling | 125% | 110% | 131% |
445.gobmk | Game AI | 125% | 150% | 127% |
456.hmmer | Protein seq. analyses | 127% | 125% | 125% |
458.sjeng | Chess | 120% | 151% | 125% |
462.libquantum | Quantum sim | 91% | 129% | 90% |
464.h264ref | Video encoding | 101% | 112% | 112% |
471.omnetpp | Network sim | 109% | 116% | 103% |
473.astar | Pathfinding | 140% | 149% | 137% |
483.xalancbmk | XML processing | 120% | 107% | 116% |
On average, both Xeons pick up about 20% due to SMT (Hyperthreading). The EPYC 7601 improved by even more: it gets a 28% boost on average. There are many possible explanations for this, but two are the most likely. In the situation where AMD's single threaded IPC is very low because it is waiting on the high latency of a further away L3-cache (>8 MB), a second thread makes sure that the CPU resources can be put to better use (like compression, the network sim). Secondly, we saw that AMD core is capable of extracting more memory bandwidth in lightly threaded scenarios. This might help in the benchmarks that stress the DRAM (like video encoding, quantum sim).
Nevertheless, kudos to the AMD engineers. Their first SMT implementation is very well done and offers a tangible throughput increase.
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CajunArson - Tuesday, July 11, 2017 - link
Would a high-end server that was built in 2014 necessarily update? Maybe not.Should a high-end server with a brand new microarchitecture use the most recent version of the software if it has any expectation of seeing a real benefit? Absolutely.
If this was a GPU review and Anandtech used 2 year old drivers on a new GPU (assuming they even worked at all) we wouldn't even be having this conversation.
BrokenCrayons - Tuesday, July 11, 2017 - link
Home users playing video games are in a different environment than you find in a business datacenter. There's a lot less money to be lost when a driver update causes a performance regression or eliminates a feature. Conversely, needlessly updating software in the aforementioned datacenter can result in the loss of many millions if something goes wrong.wallysb01 - Tuesday, July 11, 2017 - link
Conversely, having stuff working, but unnecessarily slowly costs money as well. Its a balance, and if you're spending hundreds of thousands or even millions on a cluster/data center/what have you, you'd probably want to spend at least a little bit of time optimizing it, right?Icehawk - Tuesday, July 11, 2017 - link
Most of the businesses I have worked for, ranging from 10 people to 50k, use severely outdated software and the barest minimum of patching. Optimization? HA!For example I work for a manufacturer & retailer currently, our POS system was last patched in 2012 by the vendor and has been replaced by at least two versions newer. We have XP machines in each of our stores as that is the only OS that can run the software.
The above is very typical. The 50k company I worked for had software so old and deeply entrenched that modernizing it is virtually impossible. My current company is working on getting to a new product... that was new in 2012 and has also been replaced with a newer version. Whee!
Icehawk - Tuesday, July 11, 2017 - link
One other thing - maybe the big shops actually do test/size but none of the places I have worked at and have been involved in do any testing, benchmarking, etc. They just buy whatever their preferred vendor gives them that meets the budget and they *think* will work. My coworker is in charge (lol) of selecting servers for a new office... he has no clue what anything in this article is. He has never read a single review, overview, or test of a processor. I could keep going on like this :(0ldman79 - Wednesday, July 12, 2017 - link
Icehawk's comments are so accurate it is scary.I can't tell you how many businesses running custom *nix software running in a VM on a Windows server.
They're not all about speed. Reliability is the single most important factor, speed is somewhere down the line. The people that make those decisions and the people that drink coffee while they're waiting on the machines are very different.
Neither understand that it could all be done so much better and almost all of them are utterly terrified at the concept of speeding up the process if it means *any* changes are made.
JohanAnandtech - Friday, July 21, 2017 - link
We did test with NAMD 2.12 (Dec 2016).sutamatamasu - Tuesday, July 11, 2017 - link
Glad, AMD make back again to this segment, now we can only see what can Raja to do for server market with Radeon instinct.Kaotika - Tuesday, July 11, 2017 - link
So this confirms that the previous information regarding Skylake-X core configurations was wrong, and 12-core variant is in fact using HCC-core instead of LCC-core?Ian Cutress - Tuesday, July 11, 2017 - link
We corrected that in our Skylake-X review.