linuxaudio.org

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nice has absolutely nothing to do with this, and if it has any effect, it

is accidental and should not be relied on.
On Sun, Dec 2, 2012 at 7:50 PM, jim  wrote:
>

quoted text
>     You probably tried using the  nice  command,

> maybe with most processes +10 and with -10 for

> your music processes, yes?

>

>

>

>

> On Sun, 2012-12-02 at 13:00 -0800, Ken Restivo wrote:

> > OK, I know I've been using Linux audio for 6 years now, and gigged and

> recorded with it extensively for most of those, yadda yadda. But it seems

> I've had an embarassingly huge hole in my knowledge the whole time.

> >

> > I was under the impression that, in order to use real time

> priorities/permissions and Ingo kernels, it was required for the process

> ITSELF early in the main() routine of its source code, to make some system

> calls to claim RT priority. In fact, I specifically remember reading or

> even writing source code in C which did that (probably based on JACK sample

> code). I don't recall the name of the syscall, but it was something obvious

> and well-documented.

> >

> > Also, I remember that it was also required that the software behave

> properly in order to be real-time capable, something about callbacks taking

> some predictable amount of time. Or perhaps that was only a JACK

> requirement.

> >

> > Why am I asking these dumb-ass questions now? Because I've been playing

> around with Liquidsoap and Airtime for some radio stations, and I'm

> obsessed with getting them as rock-solid on cheap/free/old hardware as I'd

> been able to get with my gigging and studio synths.

> >

> > It physically pains me to hear audio stuttering because Apache is

> running on the same box. It seems an outrage to me. Shouldn't happen. Ever.

> I used to record and mix multi-track songs in Ardour with tons of

> soft-synths WHILE A KERNEL COMPILE WAS GOING ON THE SAME MACHINE without a

> single glitch. I expect no less.

> >

> > So I asked on the Liquidsoap list, and I got only shrugs and a pointer

> to the Gentoo page in response (why? I have no idea. I use Debian, and

> that's irrelevant to the question at hand anyway.).

> >

> > So what's the deal? Is there a way to give Ingo-approved preemptive RT

> priority to things that aren't real-time apps and aren't specifically

> architected for that? What, if anything, would break?

> >

> > And, if I wanted to hack Liquidsoap (which would require learning ML,

> which wouldn't be a bad thing to know anyway), is it even possible to get

> it RT-capable, or are there low-level C system calls required in order to

> make that work?

> >

> > Sorry for the long and obscure question, but it's been bothering me for

> a while, and I figured someone here would know the answer, or where I might

> find it.

> >

> > Thanks.

> >

> >

> > -ken

> > _______________________________________________

> > Linux-audio-user mailing list

> > Linux-audio-user@lists.linuxaudio.org

> > http://lists.linuxaudio.org/listinfo/linux-audio-user

>

>

> _______________________________________________

> Linux-audio-user mailing list

> Linux-audio-user@lists.linuxaudio.org

> http://lists.linuxaudio.org/listinfo/linux-audio-user

>

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Content-Type: text/html; charset=ISO-8859-1

Content-Transfer-Encoding: quoted-printable
nice has absolutely nothing to do with this, and if it has any effect, it i=

s accidental and should not be relied on.On Sun, Dec 2, 2012 at 7:50 PM, jim <jim@well.c=

om> wrote:
=A0 =A0 You probably tried using the =A0nice =A0command,

maybe with most processes +10 and with -10 for

your music processes, yes?
On Sun, 2012-12-02 at 13:00 -0800, Ken Restivo wrote:

quoted text
> OK, I know I've been using Linux audio for 6 years now, and gigged=

 and recorded with it extensively for most of those, yadda yadda. But it se=

ems I've had an embarassingly huge hole in my knowledge the whole time.=

>

quoted text
> I was under the impression that, in order to use real time priorities/=

permissions and Ingo kernels, it was required for the process ITSELF early =

in the main() routine of its source code, to make some system calls to clai=

m RT priority. In fact, I specifically remember reading or even writing sou=

rce code in C which did that (probably based on JACK sample code). I don&#3=

9;t recall the name of the syscall, but it was something obvious and well-d=

ocumented.

>

quoted text
> Also, I remember that it was also required that the software behave pr=

operly in order to be real-time capable, something about callbacks taking s=

ome predictable amount of time. Or perhaps that was only a JACK requirement=

.

>

quoted text
> Why am I asking these dumb-ass questions now? Because I've been pl=

aying around with Liquidsoap and Airtime for some radio stations, and I&#39=

;m obsessed with getting them as rock-solid on cheap/free/old hardware as I=

'd been able to get with my gigging and studio synths.

>

quoted text
> It physically pains me to hear audio stuttering because Apache is runn=

ing on the same box. It seems an outrage to me. Shouldn't happen. Ever.=

 I used to record and mix multi-track songs in Ardour with tons of soft-syn=

ths WHILE A KERNEL COMPILE WAS GOING ON THE SAME MACHINE without a single g=

litch. I expect no less.

>

quoted text
> So I asked on the Liquidsoap list, and I got only shrugs and a pointer=

 to the Gentoo page in response (why? I have no idea. I use Debian, and tha=

t's irrelevant to the question at hand anyway.).

quoted text
>

> So what's the deal? Is there a way to give Ingo-approved preemptiv=

e RT priority to things that aren't real-time apps and aren't speci=

fically architected for that? What, if anything, would break?

quoted text
>

> And, if I wanted to hack Liquidsoap (which would require learning ML, =

which wouldn't be a bad thing to know anyway), is it even possible to g=

et it RT-capable, or are there low-level C system calls required in order t=

o make that work?

>

quoted text
> Sorry for the long and obscure question, but it's been bothering m=

e for a while, and I figured someone here would know the answer, or where I=

 might find it.

quoted text
>

> Thanks.

>

>

> -ken

> _______________________________________________

> Linux-audio-user mailing list

> Linux-audio-u=

ser@lists.linuxaudio.org

quoted text
> http://lists.linuxaudio.org/listinfo/linux-audio-user

_______________________________________________

Linux-audio-user mailing list

Linux-audio-user@l=

ists.linuxaudio.org

http://lists.linuxaudio.org/listinfo/linux-audio-user
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