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. 

Single Threaded Integer Performance: SPEC CPU2006 Multi-core SPEC CPU2006
POST A COMMENT

219 Comments

View All Comments

  • Shankar1962 - Thursday, July 13, 2017 - link

    So you think Intel won't release anything new again by then? Intel would be ready for cascadelake by then. None of the big players won't switch to AMD. Skylake alone is enough to beat epyc handsomely and cascadelake will just blow epyc. Its funny people are looking at lab results when real workloads are showing 1.5-1.7x speed improvement Reply
  • PixyMisa - Saturday, July 15, 2017 - link

    This IS comparing AMD to Intel's newest CPUs, you idiot. Skylake loses to Epyc outright on many workloads, and is destroyed by Epyc on TCO. Reply
  • Shankar1962 - Sunday, July 16, 2017 - link

    Mind your language asshole
    Either continue the debate or find another place for your shit and ur language
    Real workloads don't happen in the labs you moron
    Real workloads are specific to each company and Intel is ahead either way
    If you have the guts come out with Q3 Q4 2017 and 2018 revenues from AMD
    If you come back debating epyc won over skylake if AMD gets 5-10% share then i pity your common sense and your analysis
    You are a bigger idiot because you spoiled a healthy thread where people were taking sides by presenting technical perspective
    Reply
  • PixyMisa - Tuesday, July 25, 2017 - link

    I'm sorry you're an idiot. Reply
  • Shankar1962 - Thursday, July 13, 2017 - link

    Does not matter. We can debate this forever but Intel is just ahead and better optimized for real world workloads. Nvidia i agree is a potential threat and ahead in AI workloads which is the future but AMD is just an unnecessary hype. Since the fan boys are so excited with lab results (funny) lets look at Q3,Q4 results to see how many are ordering to test it for future deployment. Reply
  • martinpw - Wednesday, July 12, 2017 - link

    I'm curious about the clock speed reduction with AVX-512. If code makes use of these instructions and gets a speedup, will all other code slow down due to lower overall clock speeds? In other words, how much AVX-512 do you have to use before things start clocking down? It feels like it might be a risk that AVX-512 may actually be counterproductive if not used heavily. Reply
  • msroadkill612 - Wednesday, July 12, 2017 - link

    (sorry if a repost)

    Well yeah, but this is where it starts getting weird - 4-6 vega gpuS, hbm2 ram & huge raid nvme , all on the second socket of your 32 core, c/gpu compute ~Epyc server:

    https://marketrealist.imgix.net/uploads/2017/07/A1...

    from

    http://marketrealist.com/2017/07/how-amd-plans-to-...

    All these fabric linked processors, can interact independently of the system bus. Most data seems to get point to point in 2 hops, at about 40GBps bi-directional (~40 pcie3 lanes, which would need many hops), and can be combined to 160GBps - as i recall.

    Suitably custom hot rodded for fabric rather than pcie3, the nvme quad arrays could reach 16MBps sequential imo on epycs/vegaS native nvme ports.

    To the extent that gpuS are increasing their role in big servers, intel and nvidea simply have no answer to amd in the bulk of this market segment.
    Reply
  • davide445 - Wednesday, July 12, 2017 - link

    Finally real competition in the HPC market. Waiting for the next top500 AMD powered supercomputer. Reply
  • Shankar1962 - Wednesday, July 12, 2017 - link

    Intel makes $60billion a year and its official that Skylake was shipping from Feb17 so i do not understand this excitement from AMD fan boys......if it is so good can we discuss the quarterly revenues between these companies? Why is AMD selling for very low prices when you claim superior performance over Intel? You can charge less but almost 40-50% cheap compared to Intel really?
    AMD exists because they are always inferior and can beat Intel only by selling for low prices and that too for what gaining 5-10% market which is just a matter of time before Intel releases more SKUs to grab it back
    What about the software optimizations and extra BOM if someone switches to AMD?
    What if AMD goes into hibernation like they did in last 5-6years?
    Can you mention one innovation from AMD that changed the world?
    Intel is a leader and all the technology we enjoy today happenned because of Intel technology.
    Intel is a data center giant have head start have the resources money acquisitions like altera mobileeye movidus infineon nirvana etc and its just impossible that they will lose
    Even if all the competent combines Intel will maintain atleast 80% share even 10years from now
    Reply
  • Shankar1962 - Wednesday, July 12, 2017 - link

    To add on
    No one cares about these lab tests. Let's talk about the real world work loads.
    Look at what Google AWS ATT etc has to say as they already switched to xeon sky lake
    We should not really be debating if we have the clarity that we are talking about AMD getting just 5% -10% share by selling high end products they have for cheap prices....they fo not make too much money by doing that.....they have no other option as thats the only way they can dream of a 5-10% market share
    For Analogy think Intel in semiconductor as Apple in selling smartphones
    Intel has gross margins of ~63%
    They have a solid product portfolio technologies and roadmap .....we can debate this forever but the revenues profits innovations and history between these companies can answer everything
    Reply

Log in

Don't have an account? Sign up now