[Lazarus] How to program with time in milliseconds?
Mark Morgan Lloyd
markMLl.lazarus at telemetry.co.uk
Tue May 13 11:41:07 CEST 2014
Michael Schnell wrote:
> On 05/13/2014 10:45 AM, Mark Morgan Lloyd wrote:
>>
>> There's an obvious pitfall there: a poor implementation might /think/
>> that it's directly accessing the counters when in actual fact it's
>> being virtualised or fixed up by a signal handler.
>
> Regarding just reading the "performance-monitoring counter" Register
> (not creating a timer event e.g. by means of a signal) it seemingly just
> depends on the allowance bit that is (or is no) set by the os if or if
> not this can be done in user mode. Of course we would need a guaranteed
> behavior of an Arch/OS to do a viable implementation
Plus confidence that it wasn't being emulated slowly in a virtualisation
layer.
--
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]
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