[PlanetCCRMA] Reliable version of Fedora using rt-kernel?

[Fernando Lopez-Lezcano]

On 11/15/2011 09:02 AM, John S. Dey wrote:
> Hi Fernando,
>
> With the planetccrma-rt-permissions, after fixing what appears to me as a bug, I was able to start jackd in user mode.  I edited the file 99-rt-permissions.conf by changing jack-user to jackuser and logged out and back in.

Bug indeed, I just fixed that in a new version... thanks for the feedback!

> I am now running with a latency of 5.33ms with reasonable results. By the way--when I changed priorities from 20 to 99 in 99-jack.conf my system started malfunctioning, e.g., I could not get the terminal window application to start.  I corrected the situation by booting in single mode and changing the file back.

Hmm, that is strange.

> Thanks for all your assistance.  Won't it be great when all the real-time stuff gets added to the trunk of linux.  I thought it would have happened long before now.

It is a long, slow process. But we are better off than before and the rt 
patch itself keeps getting smaller as bits of it are integrated into 
mainline (thanks to the kernel gurus that keep working on it). At some 
point it will be all in, and then we'll have to convince distributions 
to make that a default in their kernel configurations, I don't 
anticipate that being easy either :-)

-- Fernando


> On Nov 14, 2011, at 9:41 PM, Fernando Lopez-Lezcano wrote:
>
>> On 11/14/2011 05:40 PM, Fernando Lopez-Lezcano wrote:
>>> On 11/14/2011 04:49 PM, John S. Dey wrote:
>>>> Fernando,
>>>>
>>>> Could the file 99-jack.conf in the same directory be causing my problem?
>>
>> You could try a new package I released that will set the permissions for you. You can install:
>>
>>   yum install planetccrma-rt-permissions
>>
>> That will give high priority scheduling (up to 99) and 4G of memory locking only to users that belong to the group "jack-rt" (make sure you are in that group!)
>>
>> Or:
>>
>>   yum install planetccrma-rt-permissions-all
>>
>> Which will give permissions to all users (might open security problems although I have not had that happen to me).
>>
>> You will need to logout and login again to test if it works. I only tested the -all package on fc16 and it seems to work for me.
>>
>> Let me know how it goes.
>> -- Fernando
>>
>>
>>>> It contains:
>>>>
>>>> ----------
>>>> # Default limits for users of jack-audio-connection-kit
>>>>
>>>> @jackuser - rtprio 20
>>>> @jackuser - memlock 4194304
>>>>
>>>> @pulse-rt - rtprio 20
>>>> @pulse-rt - nice -20
>>>>
>>>> -----------
>>>
>>> Hmmm, maybe it is overriding? (I imagine 'p' would be after 'j').
>>>
>>> Could you edit that file and change rtprio from 20 to 99?
>>> A quick test could also be to start jack with:
>>>
>>> jackd -R -P 15 -d alsa -d hw:0 ... etc ...
>>>
>>> (ie: setting priority by hand to 15 instead of the default of 60 for rt
>>> kernels - not the best choice but it would enable you to run "-R")
>>>
>>> -- Fernando
>>>
>>> _______________________________________________
>>> PlanetCCRMA mailing list
>>> PlanetCCRMA at ccrma.stanford.edu
>>> http://ccrma-mail.stanford.edu/mailman/listinfo/planetccrma
>