Ice Lake energy efficiency regression?

By: Daniel B (fejenagy.delete@this.gmail.com), May 12, 2021 6:52 am
Room: Moderated Discussions
When I first read the Anandtech analysis of Ice Lake, it seemed fairly favourable despite the competitive disadvantage. The test's conclusion was that there should be a significant performance and efficiency uplift.
Looking at the limited SPEC submissions so far, however, it seems to me that Intel's vanilla 10nm (1274) process is struggling not simply for yield but is pushing up against a steep voltage-frequency curve. Re-reading Anand's test, it is now becoming clear that the high-end 8380 trades off a great deal of efficiency for peak performance to a degree that it undermines system efficiency. What wasn't replicated at Anand is the regression for efficiency, so probably we need to wait for further SPEC submissions.

It is rather not trivial for me to normalize it for all the moving parts to make a fair node comparison, but the picture is not encouraging either way.

Fujitsu SUSE submissions:

Top-bin 28C Cascade Lake 8280L - 13,502 blended and 16,028 @70%
http://spec.org/power_ssj2008/results/res2019q2/power_ssj2008-20190423-00958.html

Top-Bin 40C Ice Lake 8380 - 11,533 blended and 13,917 @70%
http://spec.org/power_ssj2008/results/res2021q2/power_ssj2008-20210407-01093.html

That's a 15% drop in power efficiency. According to Fujitsu, the change in Java contributes to this drop, but wouldn't account for all of it, Ice Lake could be 10% better maybe. There is the question of more memory channels and more DIMMs, adding to power. Configuring Ice Lake to lower TDP would at best buy 10% efficiency, my estimation. Even then, Ice Lake would not deliver a meaningful improvement despite updated uarch, more cores, new node. Two SPEC CPU Energy submissions also indicated a regression from Cooper Lake to Ice Lake at 10% drop. Worse still, it is around Broadwell.

That's sort of unprecedented in the past 15 years. Looks like 10nm efficiency is crippled without the SuperFin upgrade, which probably came too late for Ice Lake to be ported to.

Where am I wrong? Thoughts?

 Next Post in Thread >
TopicPosted ByDate
Ice Lake energy efficiency regression?Daniel B2021/05/12 06:52 AM
  Ice Lake energy efficiency regression?Tim2021/05/12 11:10 AM
  Ice Lake energy efficiency regression?Adrian2021/05/12 11:22 AM
  Ice Lake energy efficiency regression?Groo2021/05/12 07:23 PM
    cloud binsDaniel B2021/05/13 06:19 AM
      cloud binsJames2021/05/13 06:43 AM
        cloud binsGroo2021/05/13 07:48 AM
      cloud binsGroo2021/05/13 07:39 AM
        cloud binsMichael S2021/05/13 12:00 PM
          cloud binsGroo2021/05/14 08:09 AM
Reply to this Topic
Name:
Email:
Topic:
Body: No Text
How do you spell avocado?