[LAD] [Jack-Devel] jack2's dbus name

Jussi Laako jussi at sonarnerd.net
Thu Jun 18 17:12:09 UTC 2009

Lennart Poettering wrote:
> PA does not use fixed block sizes. We always use the largest chunk
> sizes the applications pass to us and break them up into smaller
> pieces only when really necessary. We really try our best not having
> to touch/convert/split/copy user supplied PCM data if we don't have
> to.

This is quite different from the goals of JACK, where the purpose is to
minimize input -> output latency and thus use as small as possible blocks.

Typically there's:

[input] --> [processing] --> [output]
            [generation] --^

Where input is typically live sound or MIDI, processing can be effects
processing or similar (guitar distortion or such) while generator can be
a softsynth, beatbox or something similar. Both have to naturally run
precisely in-sync. While minimizing the latency from input to output is
crucial for playing and has to run in-sync with all the rest of the
softsynths. Playing a piano with couple of notes lag before you hear the
sound is annoying...

	- Jussi

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