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by gwd 1549 days ago
> Intel rested on their laurels because AMD almost wiped themselves out

You mean, Intel almost illegally wiped AMD out using its monopoly position in the x86 market:

https://www.amd.com/en/corporate/antitrust-ruling

1 comments

Bulldozer was terrible
The meltdown/spectre mitigations have wiped out most of the gap between bulldozer chips and the contemporary Intel ones.

Did Bulldozer really lose or was the competition cheating?

> Did Bulldozer really lose or was the competition cheating?

Bulldozer and it’s competition were both designed at a time where leaking information to another process on the same physical core was outside the threat profile CPU memory protection was designed to mitigate against. Intel was optimizing aggressively within the envelope of expectations at the time, which were upended by the rise of cloud computing.

Big citation needed there.

Spectre mitigations shouldn't effect quite a lot of programs because there's nothing to mitigate within the same address space.

https://www.phoronix.com/scan.php?page=article&item=spectre-...

Worst case I see is approximately 33% performance penalty in aggregate for Xeon parts, with much worse performance in specific scenarios. Comparing the original Bulldozer benchmarks, this does close the gap like GP suggested.

Also, refresh your memory on how the mitigations work because there’s definitely an impact for most programs.

Ok yes I was too black and white, but still a lot of programs should be OK. You need to harden web browsers differently to (say) a calculator.

Also bulldozer is almost definitely vulnerable to spectre.

Hard to innovate properly when your income stream is artificially restricted.
Then how did Ryzen work?
Semi-custom (aka console) chips kept them afloat, and they executed well on Ryzen while Intel made modest year-over-year improvements. Doesn't mean they weren't working on a relatively tight R&D budget, though.
Ryzen worked in part because it didn't try to be super-clever. Bulldozer was very opinionated about how computing would look (cheap cpu + big coprocessor) whereas Zen is much more practical