Re: [PATCH,RFC] random: collect cpu randomness

[JÃrn Engel]

On Sun, 2 February 2014 20:39:22 -0500, Theodore Ts'o wrote:
> 
> The real question is how much overhead does it add, and is it worth
> it.  JÃrn, I take it that was the reason for creating an even faster,
> but weaker mixing function?  Was the existing "fast mix" causing a
> measurable overhead, or was this your just being really paranoid about
> not adding anything to the various kernel fastpaths?

It was paranoia.  And I am still somewhat paranoid and don't trust my
benchmark results yet.  Maybe on an 1024-CPU Altix with a 100k-thread
workload the overhead is too much.  Just because I couldn't measure a
difference on my wimpy notebook does not mean much.

JÃrn

--
One of the painful things about our time is that those who feel certainty
are stupid, and those with any imagination and understanding are filled
with doubt and indecision.
-- Bertrand Russell
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