[LAU] RTC/HPET timer permissions

Ralf Mardorf ralf.mardorf at alice-dsl.net
Tue Nov 27 11:38:56 UTC 2012


On Tue, 2012-11-27 at 11:40 +0100, Jeremy Jongepier wrote:
> Software like Qtractor can use it too when the module is loaded. Is
> this recommended? Does it improve MIDI timing for instance? How does
> it compare to the default timer setting?

If you use hardware MIDI the different PCM timers or
hr timer can improve jitter or sync between audio and MIDI or whatever,
at least it results in different drift for MIDI and audio, if you record
e.g. one MIDI channel after the other using hardware MIDI.

Usually system timer (default) is the best way to go,
hr timer is better, but can cause issues, PCM timer should be less good,
but there could be some voodoo when using it, that could improve things.

If you don't use hardware MIDI don't care about it and use default,
resp. system timer.

This is what I experienced. Sometimes people fall out a plane when
flying very high, without a parachute and they survive. There's no
rational explanation.

"Default" is default for good reasons, to have other options can help,
but if you don't have issues, there's no reason to care about those
optional timers.

Regards,
Ralf




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