[Beowulf] Intel CPU design bug & security flaw - kernel fix imposes performance penalty

[Christopher Samuel]

Hi all,

Just a quick break from my holiday in Philadelphia (swapped forecast 40C
on Saturday in Melbourne for -10C forecast here) to let folks know about
what looks like a longstanding Intel CPU design flaw that has security
implications.

There appears to be no microcode fix possible and the kernel fix will
incur a significant performance penalty, people are talking about in the
range of 5%-30% depending on the generation of the CPU. :-(

https://www.theregister.co.uk/2018/01/02/intel_cpu_design_flaw/

There's a post on the PostgreSQL site that measures the impact, El Reg
summarises the impact as:

https://twitter.com/TheRegister/status/948342806367518720?ref_src=twsrc%5Etfw

Best case: 17% slowdown
Worst case: 23%

Here's the post about the measured impact:

https://www.postgresql.org/message-id/20180102222354.qikjmf7dvnjgbkxe@alap3.anarazel.de

This is going to be interesting I think...

All the best,
Chris
-- 
  Chris Samuel  :  http://www.csamuel.org/  :  Melbourne, VIC