Re: [linux-audio-user] rlimit problem on opensuse 10.0 - maybe first part of a solution

On Fri, 06 Jan 2006 01:01:51 +0100
Joern Nettingsmeier <nettings@email-addr-hidden-hochschule.de> wrote:

> hi everyone!
>
>
> after some time of job-induced absence from audio work, i have tried
> to bring my audio workstation up to date again.
>
> the problem is that i can't get realtime privileges.
>
> arch is x86_64, distro is opensuse 10.0, i'm using the distro kernel,
> which is a 2.6.13 with additional patches.
>
> my /etc/security/limits.conf:
>
> @realtime - memlock 128000
> @realtime - nice 10
> @realtime - rtprio 70
>
> the account i use is member of @realtime.
>
> on login, i get
>
> Jan 6 00:01:38 kleineronkel pam_limits[13812]: unknown limit item
> 'nice' Jan 6 00:01:38 kleineronkel pam_limits[13812]: unknown limit
> item 'rtprio'
>

Hi people!

I finally got pam rt rlimits working, using pam 0.78 + rlimits patch on
a gentoo system. Jack starts fine in realtime. rt-lsm not loaded.

But there are some questions i'd like to ask, well.. one that is. And i
think this might also be the issue mentioned here.

all docs around the net tell that one has to set following in
limits.conf:
@audio - memlock 250000
@audio - nice -10
@audio - rtprio 100

..or @audio whatever. now i also got that unknown item 'rtprio' on
login from pam.

looking at the patch i found the following:

@@ -293,6 +298,10 @@
     else if (strcmp(lim_item, "locks") == 0)
        limit_item = RLIMIT_LOCKS;
 #endif
+ else if (strcmp(lim_item, "rt_priority") == 0)
+ limit_item = RLIMIT_RTPRIO;
+ else if (strcmp(lim_item, "nice") == 0)
+ limit_item = RLIMIT_NICE;
     else if (strcmp(lim_item, "maxlogins") == 0) {
        limit_item = LIMIT_LOGIN;

now even i'm not a coder, rtprio is infact called rt_priority! that
seems dokumented wrong in limits.conf on opensuse

also i've read that for audio one should set, hehe --> rt_priority to
100, which seems not to make much sense as:

+ case RLIMIT_RTPRIO:
+ if (limit_value > 99)
+ limit_value = 99;
+ if (limit_value < 0)
+ limit_value = 0;
+ break;

^^ 99% is the (stochastical) limit

Maybe that helps some people here! If i got something wrong please
excuse and correct me. At least here it now all seems to work out fine
and also audio apps can now use more than 15% cpu, which is set as
default value in the patch.

Best regards
Tom
Received on Thu Jan 12 04:15:05 2006