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

[Greg Lindahl]

On Wed, Jan 03, 2018 at 02:46:07PM +1100, Christopher Samuel wrote:

> 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. :-(

The performance hit (at least for the current patches) is related to
system calls, which HPC programs using networking gear like OmniPath
or Infiniband don't do much of.

-- greg