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Does anyone know of any benchmarks that go through the full impacts for all of Intel’s hardware-level security issues? I remember seeing the Linux kernel devs

by sq_ 7y ago

Does anyone know of any benchmarks that go through the full impacts for all of Intel’s hardware-level security issues? I remember seeing the Linux kernel devs discussing some massive 10+% performance hits back around Meltdown/Spectre patch time, and I’m now wondering what the final impact has been.

okanesen 7y ago
I don't know about full pre and post benchmarks but there is the latest benchmark from Phoronix which benchmarks the latest Spectre "SWAPGS" mitigations [0]. [0]: https://www.phoronix.com/scan.php?page=article&item=swapgs-spectre-impact&num=1 https://www.phoronix.com/scan.php?page=article&item=swapgs-s...
mrep 7y ago
10 percent? My teams RDS cpu usage spiked up by 40 percent after the initial patch [0]. [0]: https://m.imgur.com/a/khGxU https://m.imgur.com/a/khGxU
- sq_ 7y ago
  Oh wow. That's a lot worse than I'd expected. Intel really royally screwed up, especially since so much of their current optimization relies on the same hardware functionality that makes these side-channel attacks possible.
- hajile 7y ago
  Epic Games saw their CPU usage double after applying the meltdown patch. Things have gotten quite a bit slower since then. Turns out flushing every time you switch into kernel space carries a massive impact if you are realtime with lots of network calls. https://web.archive.org/web/20180106011413/https://www.epicgames.com/fortnite/forums/news/announcements/132642-epic-services-stability-update https://web.archive.org/web/20180106011413/https://www.epicg...
- msh 7y ago
  What is RDS short for?
  - mrep 7y ago
    Amazon web services relational database service: https://aws.amazon.com/rds/ https://aws.amazon.com/rds/
toast0 7y ago
The impacts really depend on your use case. The mitigations make each context switch have a much higher fixed cost. If you're doing something that's syscall heavy, you're going to see a big negative difference. If it's something that's CPU heavy without making many syscalls, you're not going to see a lot of difference.

by sq_ 7y ago

okanesen 7y ago

I don't know about full pre and post benchmarks but there is the latest benchmark from Phoronix which benchmarks the latest Spectre "SWAPGS" mitigations [0]. [0]: https://www.phoronix.com/scan.php?page=article&item=swapgs-spectre-impact&num=1 https://www.phoronix.com/scan.php?page=article&item=swapgs-s...

mrep 7y ago

10 percent? My teams RDS cpu usage spiked up by 40 percent after the initial patch [0]. [0]: https://m.imgur.com/a/khGxU https://m.imgur.com/a/khGxU

sq_ 7y ago
Oh wow. That's a lot worse than I'd expected. Intel really royally screwed up, especially since so much of their current optimization relies on the same hardware functionality that makes these side-channel attacks possible.
hajile 7y ago
Epic Games saw their CPU usage double after applying the meltdown patch. Things have gotten quite a bit slower since then. Turns out flushing every time you switch into kernel space carries a massive impact if you are realtime with lots of network calls. https://web.archive.org/web/20180106011413/https://www.epicgames.com/fortnite/forums/news/announcements/132642-epic-services-stability-update https://web.archive.org/web/20180106011413/https://www.epicg...
msh 7y ago
What is RDS short for?
- mrep 7y ago
  Amazon web services relational database service: https://aws.amazon.com/rds/ https://aws.amazon.com/rds/

toast0 7y ago

The impacts really depend on your use case. The mitigations make each context switch have a much higher fixed cost. If you're doing something that's syscall heavy, you're going to see a big negative difference. If it's something that's CPU heavy without making many syscalls, you're not going to see a lot of difference.