[linux-audio-dev] [ANN] JACK Rack 1.4.1

Paul Davis paul at linuxaudiosystems.com
Thu Feb 20 10:54:00 UTC 2003


>> >* midi thread will now try and use SCHED_FIFO.  If you run jackd with
>> 
>> why?
>
>Without SCHED_FIFO, the midi thread takes a back seat in the
>processing.  This means that control changes come in chunks, causing big
>jumps in the plugins' controls settings.  This makes clicks and pops and
>stuff, it doesn't reflect what happening in real-time, and is generally
>not very nice.

but this is true of the GUI controls too, right? do you propose to run
that at SCHED_FIFO (which will make no difference unless the X server
is as well)?

jumps in control values should always be interpolated by the plugin
unless such jumps are OK (e.g. a discrete "switch-like" control). it
should be possible to set a control port to its min value and then on
the next run() call have it set to the max value and get no clicks.

this stuff is not the domain of the UI/MIDI thread, really, though i
see your point in cases where the CPU is close to maxxed out by the
plugin cycles. it doesn't make for a very nice HCI experience.

not sure about this one ...

--p





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