[systemd-devel] Real Time access in a systemd control group

[Marius Perjeru]

Hi,

We configured a systemd environment, but we cannot have real time access 
when running an application.

We have defined a xorg.service which starts the X, and every script 
runned gets under systemd/xorg.service control group, and because this 
control group does not have real time access (cpu.rt_runtime_us contains 
0 value), we cannot run real time applications.

I tryied to create a system_at_marius.service containing:
[Unit]
Description=Systemd for marius user

[Service]
User=marius
PAMName=systemd
ExecStart=/bin/systemd --user

[Install]
WantedBy=multi-user.target

But it won't start:
Starting Systemd for marius user...
<29>systemd[1]: systemd_at_marius.service: main process exited, 
code=exited, status=1
<29>systemd[1]: Unit systemd_at_marius.service entered failed state.

Is there anyway that I could give real time access to some control 
groups (or services)? I know there is LimitRTTIME variable which I set 
it to infinity, but the behavior does not change.

I also tried to create a realtime group, added it to 
/etc/security/limits.d/99-realtime.conf
@realtime   -  rtprio    99
@realtime   -  memlock   unlimited

And add marius user to this group. But that also did not change anything.

Best Regards,
Marius