[LAD] Some questions about the Jack callback

Len Ovens len at ovenwerks.net
Sat Sep 20 06:16:38 UTC 2014

On Fri, 19 Sep 2014, Will Godfrey wrote:

> Say we have A, B & C in that order and B&C each take 3mS to return but A 
> takes 6mS. Does C get booted out even though it was A that was the time 
> hog?

The expectation is that, there is enough time to finish a,b and c all the 
time. Otherwise there is an xrun. This means that no matter which one 
takes too much time there may be an audible glitch. The answer is to use 
greater latency, faster processor, or fewer/different clients. Perhaps a 
better question is if it would be possible to know the time taken by each 
of the clients so the user could make an informed decision as to which 
client to remove... but it could be that the client with the longest time 
is also the most important.

Is it really a good idea to try to fix the problems of another client by 
doing something that may end up being more audible? Even straight bypass 
may be audible if the client changes the sound a great amount. That bypass 
then takes some of the time that could have been used to meet the 

Len Ovens

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