Energy Consumption

We tested the energy consumption of our servers for a one-minute period in several scenario. The first scenario is the point where the server under testing performs best in MySQL: the highest throughput just before the response time goes up significantly. 

To test the power usage of the FPU, we measure the power consumption when POV-Ray was using all available threads. 

SKU TDP
(on paper)
spec
Idle
Server

W
MySQL
Best Throughput
at Lowest Resp. Time (*)
(W)
POV-Ray
100% CPU load
Dual Xeon E5-2699 v4 2x145 W 106 412 425
Dual Xeon 8176  2x165W 190 300 453
Dual EPYC 7601 2x180W 151 321 327

Both the Xeon 8176 and Dual EPYC server had a few more additional components (a separate 10 GBe card for example) than the Dual Xeon E5-2699v4 system, but that does not fully explain why idle power is so much higher, especially on the Dual Xeon 8176. We lacked the time to fully investigate this, and the last two systems have relatively new firmware.

The only conclusion that we can draw so far, is that the EPYC 7601 is likely to draw more power when running integer applications, while the rather wide FP units of the Intel CPUs are real power hogs even if they do not run heavy AVX applications. To be continued...

Floating Point performance Closing Thoughts
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  • alpha754293 - Tuesday, July 11, 2017 - link

    Pity that OpenFOAM failed to run on Ubuntu 16.04.2 LTS. I would have been very interested in those results.
  • farmergann - Tuesday, July 11, 2017 - link

    Are you trying to hide the fact that AMD's performance per watt absolutely dominates intel's, or have you simply overlooked one of, if not the, single most important aspects of server processors?
  • Ryan Smith - Tuesday, July 11, 2017 - link

    Neither. We just had very little time to look at power consumption. It's also the metric we're the least confident in right now, as we'd like to have a better understanding of the quirks of the platform (which again takes more time).
  • Carl Bicknell - Wednesday, July 12, 2017 - link

    Ryan / Ian,
    Just to let you know there are better chess benchmarks than the one you've chosen. Stockfish is an example of a newer program which better uses modern CPU architecture.
  • NixZero - Tuesday, July 11, 2017 - link

    "AMD's MCM approach is much cheaper to manufacture. Peak memory bandwidth and capacity is quite a bit higher with 4 dies and 2 memory channels per die. However, there is no central last level cache that can perform low latency data coordination between the L2-caches of the different cores (except inside one CCX). The eight 8 MB L3-caches acts like - relatively low latency - spill over caches for the 32 L2-caches on one chip. "
    isnt skylake-x's l3 a victim cache too? and divided at 1.3mb for each core, not a monolytic one?
  • Ian Cutress - Tuesday, July 11, 2017 - link

    That's what a 'spill-over' cache is - it accepts evicted cache lines.
  • NixZero - Wednesday, July 12, 2017 - link

    so why its put as an advantage for intel cache, which is spill over too?
  • JonathanWoodruff - Wednesday, July 12, 2017 - link

    Since the Intel one is all on one die, a miss to a "slice" of cache can be filled without DRAM-like latencies from another slice. Since AMD has it's last level caches spread across dies, going to another cache looks to be equivalent latency-wise to going to DRAM. It wouldn't necessarily have to be quite that bad, and I would expect some improvement here for Zen2.
  • Martin_Schou - Tuesday, July 11, 2017 - link

    This has to be wrong:

    CPU Two EPYC 7601 (2.2 GHz, 32c, 8x8MB L3, 180W)
    RAM 512 GB (12x32 GB) Samsung DDR4-2666 @2400

    12 x 32 GB is 384 GB, and 12 sticks doesn't fit nicely into 8 channels. In all likelihood that's supposed to be 16x32 GB, as we see in the E52690
  • Dr.Neale - Tuesday, July 11, 2017 - link

    I find myself puzzled by the curious omission in this article of a key aspect of Server architecture: Data Security.

    AMD has a LOT; Intel, not so much.

    I would think this aspect of Server "Performance" would be a major consideration in choosing which company's Architecture to deploy in a Secure Server scenario. Especially in light of Recent Revelations fuelling Hacking Headlines in the news, and Dominating Discussions on various social media websites.

    How much is Data Security worth?

    A topic of EPYC consequence!

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