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Re: nacl and CPU frequency.

On 22/09/12 15:28, peter green wrote:
> In order to build successfully nacl needs to determine the CPU frequency
> (the CPU frequency determined at build time is not used in the final
> binaries afaict but if it's not determined then the build will fail as
> it will consider the implementation broken and if it can't find any
> non-broken implementations it won't build).
> Do you known how important it is to have an accurate CPU frequency
> determination for nacl. e.g. if true CPU frequency can't be determined
> would it be ok to use bogomips instead?

I can't imagine why it would want to know this --- particularly as most
modern architectures don't *have* a single clock frequency (and some may
not have clocks at all).

I wonder if what the developers were actually thinking of when they
think of a clock frequency is actually the value of CLOCKS_PER_SEC,
which is the factor needed to turn a clock_t into a real wall-clock time
--- because on Posix that's defined to be 1000000, regardless of the
actual implementation details...

┌─── dg@cowlark.com ───── http://www.cowlark.com ─────
│ life←{ ↑1 ⍵∨.^3 4=+/,¯1 0 1∘.⊖¯1 0 1∘.⌽⊂⍵ }
│ --- Conway's Game Of Life, in one line of APL

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