[systemd-devel] make systemd service takes cpu exclusively

[Andrei Borzenkov]

В Tue, 18 Nov 2014 06:25:43 +0000
"Cao, XinX" <xinx.cao at intel.com> пишет:

> Hi, Umut  & David,
> 	
> 	My project needs the Graphical desktop to display on monitor as fast as possible, but I found lots of unrelated services( such as sound, network, ... ) are competing CPU even they are explicitly After graphical service. And this competion delays the startup of graphical desktop process. So, my opinion is to make graphical related programs runs first and  the other unrelated services only starts after graphical program finished startup. 

Let me guess. Your Graphical desktop is defined of simple or forking,
right? So from systemd point of view service is started as soon as
process is forked and it proceeds with starting further service defined
After this one.

The problem with After is that it is effective only if systemd can know
when service startup is completed. And in general it is possible only
with types dbus or notify (and cooperating server). In case of GUI you
do not even have single process representing service, depending on
definition of "Graphical desktop".