
Microsoft says security fixes will noticeably slow older PCs - JohnTHaller
https://www.engadget.com/2018/01/09/microsoft-meltdown-spectre-performance-hit/
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Scaevolus
An instruction added as a curiosity / micro-optimization back in 2010 is now
_very_ important.

Previously: "PCID is now a critical performance/security feature on x86"
[https://news.ycombinator.com/item?id=16094349](https://news.ycombinator.com/item?id=16094349)

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chrishynes
Interesting that it's more substantial on older CPU's. The cynic in me wonders
if that's a way to force an upgrade from CPU's that normally would be fine for
most typical office use.

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Someone1234
This has absolutely destroyed Intel's reputation and handed a massive PR win
to their competitors (including AMD). Hard to imagine any normal company
cutting out their own feet so willingly, this will cost Intel a lot more than
it will make them in short term revenue.

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throwawayfinal
I'm not sure how they could have come out of this cleanly other than waving a
wand and not having it happen? They pretty clearly owned up.

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lovich
They sat on it for over quarter and gave no indication that any sort of
trouble was coming up. The CEO even sold stock and made a profit after being
made aware of the issue, but before having the issue be announced publicly. I
would not classify that as clearly owning up

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user5994461
>>> If you're using a 4th-generation Core or older CPU, however, you'll see
"more significant slowdowns,"

With server CPUs always being a few generations behind the desktop, this is
gonna have massive impact on datacenters.

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dragontamer
Heh. Have you seen the Phoronix benchmarks?

[https://www.phoronix.com/scan.php?page=news_item&px=KPTI-
Ret...](https://www.phoronix.com/scan.php?page=news_item&px=KPTI-Retpoline-
Combined-Ubuntu)

E3-1280 v5 goes from 32278.00 Apache requests per second to 25399.47 Requests
per second. In other words, a Skylake Xeon performs like an Fx Bulldozer after
the patch. And Skylake has the PCID instruction too.

Although to be fair, static-file hosting is about as I/O bound as it gets, and
these patches affect file I/O the most.

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lostmsu
Compile time slowdown looks pretty sad too. -21% is quite bad.

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TheSleeprAwakns
Is there any idea when this will be fixed in hardware?

