[LAU] Focusrite Saffire Pro 40 - reliable?

Len Ovens len at ovenwerks.net
Mon Mar 2 01:28:31 UTC 2015

On Sun, 1 Mar 2015, Paul Davis wrote:

>       Also it occurs to me... swappiness 10... and make sure to have enough
>       memory that no swapping ever takes place  :)  An unimportant thing
>       like a workspace pager that gets swapped out... can stop audio dead
>       if the user has the soft synth on a different workspace they need to
>       adjust.
> this should NEVER be true. if it is true then the synth is misdesigned or the
> video driver is incorrectly written.
> JACK (1) goes to some considerable lengths to make sure that the relevant code of
> its clients can never be swapped out. JACK 2 makes a similar though slightly less
> sophisticated effort.

I have worded things wrong, or not used enough words. I have not found a 
badly behaved audio program. When using multiple workspaces, the pager 
used to get from one workspace to another can get swapped out with a low 
enough swappiness. Clicking on the pager means the pager has to be moved 
into memory. The pager itself is of low priority and does not disturb the 
audio, but the kernel code (at least a few versions back when I was 
testing this stuff) that moves the pager back into memory has a higher 
priority and can stop audio on the lowlatency kernel. I may have described 
this wrong, but do remember having trouble with swapped out "minor" apps 
like the pager. (I have been told using the kb shortcut does not cause 
this problem) I have not had this trouble at all with swappiness 10... and 
almost entirely forgot about it since upgrading from 1Gram to 2.5 (and now 
8). I am to a point now where I just expect to need enough memory that 
swap does not get used.

Len Ovens

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