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by chuankl 620 days ago
There is something wrong with some of those numbers.

For example, take 7-Zip Compression 22.01. The CPU Power Consumption Monitor chart states:

AmpereOne: Average 278.72W EPYC: Average 311.64W

But the fine print under that same chart states:

AmpereOne: 6968J per run EPYC: 14439J per run

By the Joules per run numbers, AmpereOne is far more power efficient than EPYC, requiring only less than half of the energy to complete a run.

In that case, how could the average power of EPYC to be only 11.8% higher than that of AmpereOne? For this benchmark EPYC is 14.2% faster than AmpereOne, and if the average power numbers are correct, the EPYC should have slightly lower Joules per run than AmpereOne.

That is not the only anomaly. For example, the CPU Power Consumption Monitor chart for John the Ripper 2023.03.14 also does not make sense.
2 comments
rowinofwin 620 days ago
The averages are not the same as the median values, I think this is where some of the problem comes from. The plots have quartiles with the boundaries shown as lines. The line showing the median value for the Ampre system is near the middle of the plot, but the median value for the AMD plot is far over to the right end of that plot, suggesting that many of the results were in a narrow range just above that value. This would skew the total average energy consumption way up, so we would see the difference shown in average Joules per run. This is probably not a good type of plot for this type of data, a scatter plot or line chart may be better.
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telgareith 620 days ago
Heres more: * first chart has a n of 3. (Mythbusters' rocket car had n>3) * the jouls you reference have candle charts showing way too much variance to make any conclusions.

Never-mind that these are all reduced to absurd levels, or biased.

My favorite was some site crapping on a SSD that only managed 3GiB/s for 100GiB of data, then dropped to 500meg or something. But, they didn't mention data transferred at all. Just speed vs time. Obviously pushing for that higher kickback on the ssd that costs 4x as much and uses 8x the power.

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