
AMD Ryzen Threadripper 3990X Linux Performance - jjuhl
https://www.phoronix.com/scan.php?page=article&item=3990x-threadripper-linux&num=1
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pythux
I love AMD and I am super impressed with the performance of this new CPU.
Especially when comparing to top offering from Intel. But, how did they manage
to catch up on Intel? Is there a catch? How did it go so wrong for Intel?

~~~
qalmakka
As far as I've understood, it's complicated but I think some or all of the
following reasons are involved in Intel starting to lose its foothold on the
market:

\- AMD got a new very competent CEO (Lisa Su) that managed to save the company
and turn its fortunes around;

\- In the last decade, Intel seemingly forgot what its core businesses were,
and instead invested lots of its time and resources to try to break into new
markets such as smartphone CPUs and modems (failing miserably at that);

\- AMD is fabless; they got rid of their expensive fabs in the '00s by
spinning them off as GlobalFoundries. When TSMC perfected its 7nm node, they
just jumped manufacturers;

\- Intel has lost the fabs lead it had years ago; I still remember them
releasing 22nm chips while AMD was still on GloFo 45nm. Intel has been stuck
on its 14nm node for years, and they haven't been able to release 10nm chips
until last year;

\- AMD saw a clear market interest for CPUs with a higher core count, and they
managed to deliver a "good enough" CPU that appealed to buyers in a stale
market. The Ryzen R7 1700 had slightly lower single-threaded performances than
Intel, but it offered immensely better multicore performances than its Intel
equivalent for a comically low price point, on cheap motherboards and with its
stock cooler;

\- Due to almost complete lack of competition from AMD for almost a decade,
Intel got greedy and CPU prices skyrocketed; in 2017 an 8 core HEDT CPU from
Intel was sold at a price close to $1100, which is almost as much as a whole
R7 1700 setup costed. AMD had nothing to lose and no risk of market
cannibalisation, so they could just price their CPUs at much lower price point
than Intel;

\- Ryzen is arguably a good design, and AMD's idea of making high core count
CPU by interconnecting small quad-core CCXs instead of making huge dies like
Intel Xeons was a bet that really paid off. Operating systems already more or
less supported NUMA-like architectures, and AMD got from this a very scalable
architecture. Like Threadripper has shown, they can just "glue" CPUs together;
the final result is a much bigger package and a huge socket, but nobody really
cares about that.

~~~
regulation_d
I wonder if it's also fair to say that Intel was living on borrowed
performance as it relates to the Spectre style vulnerabilities. IIRC,
addressing those vulnerabilities was less impactful for AMD.

~~~
sebazzz
Meltdown is what affects Intel, in addition to the TSX issues. Spectre
affected AMD too.

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boris
Interesting how compilation benchmarks do not scale at all from 24 to 32 to 64
core Threadrippers. Neither Linux kernel nor LLVM compilation. I wonder why
it's so bad.

~~~
yxhuvud
The article mentions storage seeming to be a bottleneck.

~~~
glandium
That's not true. I've observed a kernel build not hitting all the cores at
100% with everything in a tmpfs on a 3970x. I didn't investigate why.

~~~
anonsivalley652
Showing some curiosity might help. When you learn to profile and dig deeper,
you will be able to understand what's going on, troubleshoot it and find the
bottleneck(s). I remember the kernel compiling in sub-10 seconds on Egenera's
multi-million dollar quad-socket blade racks a decade ago. Given the computing
power, memory speed, bus speed, SSD performance and code-size today, there's
no material reason similar figures shouldn't be attainable today.

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sm4rk0
What's the TDP and CPU temperatures while running those tests?

~~~
onli
Not sure about those tests, but TDP is 280W, usage a bit lower. See
[https://www.computerbase.de/2020-02/amd-ryzen-
threadripper-3...](https://www.computerbase.de/2020-02/amd-ryzen-
threadripper-3990x-test/4/#diagramm-test-leistungsaufnahme-maximale-cpu-power)
for that and [https://www.computerbase.de/2020-02/amd-ryzen-
threadripper-3...](https://www.computerbase.de/2020-02/amd-ryzen-
threadripper-3990x-test/4/#chart-groups-94300) for temps, note that this
review used a Kraken X62.

That energy usage is below the specified TDP is surprising. Some other recent
processors - especially from Intel, but to a lesser extreme also some AMD
models - happily went way above their specifications.

