Improving the kernel/i386 timecounter performance (GSoC proposal)

[Poul-Henning Kamp]

In message <20090329180745.GB38985 at server.vk2pj.dyndns.org>, Peter Jeremy write
s:

>>I'm assuming folks are still in love with the TSC because it still the
>>cheapest as oppose ACPI-fast or HPET to even contemplate this?
>
>That is its major advantage.  It might be feasible to export all the
>data necessary to implement the complete CLOCK_*_FAST family.

The general attraction is that it can be read from userland by unpriviledged
programs.

On systems where the ACPI or HPET hardware can be memory-mapped, I should
be equally possible to map those read-only into userland processes.

Now _THAT_ would be interesting.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.