[PlanetCCRMA] The JACK Story

[Fernando Lopez-Lezcano]

On Sat, 2009-11-28 at 23:16 +1300, Michael Curtis wrote:
> 
> On 24/11/2009, at 6:26 PM, Fernando Lopez-Lezcano wrote:
> 
> > On Mon, 2009-11-23 at 18:33 -0800, Jonathan Ryshpan wrote:
> > 
> > > I'd advise not to try to get Fedora to change its policies, if you
> > > can
> > > avoid it.  Such coordination is always trouble for both parties.
> > 
> > Maybe so. If a better jack makes it into Fedora it would be best
> > that it
> > could be made compatible with the rt kernel and rtirq. We'll see how
> > it
> > goes. 
> > 
> 
> Just weighing in with my 2c here.  It should be possible to patch jack
> to change the default priority at runtime based on the kernel it's
> running on.
> 
> 
> Something like
> #include <sys/utsname.h>
> 
> 
> .....
> 
> 
> {
>   struct utsname utsname;
>   int success;
> 
> 
>   success = uname( &utsname );
>   
>   if( success == 0 && strstr( utsname.version, "ccrma" ) )
>   {
>     defaultPriority = 60;
>   }
>   else
>   { 
>     defaultPriority = 20;
>   }
> }
> 
> 
> I'd would think this would be an easy patch to maintain as it would
> slot early into the options parser, which is probably something that
> is not changed frequently upstream. (note I made up the variable
> defaultPriority, so I have no idea if it's as easy as this in the Jack
> source, however I normally write a getopt parser by setting default
> values from compiled in options and then overriding them if an option
> is set, so if this is the case, it should be fairly straightforward).
> 
> 
> I suspect Fedora may frown on such detection of kernel versions but in
> my opinion this would be a good solution - even if you are using CCRMA
> but (for security / stability reasons) using a stock (Fedora) kernel,
> Jack will automagically make the right default choice.

Yes, that would work, thanks for the suggestion!
I'll try it out. 

Of course it would be better if both Planet CCRMA and Fedora would
agree. I have to look in detail at the rtirq script (it has options to
costomize things) and make it compatible with max=20 if possible. 

Thanks again!

-- Fernando