Make process non-swappable
 

Dear Linux Users


I have a netbook with Debian Wheezy and KDE installed (but question is not related to distro).
The system hangs up when I launch a program (it's not important exactly which) that consumes much memory. It happens so because all other processes (including KDM) are swapped.

Because I use the netbook in GUI mode I want KDM to be responsive all the time (and I prefer this memory-hungry process to be swapped rather than KDM). It would be great to specify that some processes (e.g. kdm) should not be swapped at all.

The questions are:
1) does this problem annoys anybody except me?
2) maybe there is a common solution (and I could not find suitable keywords to search)
3) is there any possibility of specifying that process must not be swapped at all? Of course such a feature may lead to global out-of-memory if misconfigured (e.g. if too much processes have to always be in RAM).
4) can cgroups help with this?


Regards
Roman Suvorov.

There are sysctls that control how memory is managed - but you'd need the foresight of the Oracles of Delphi to configure them correctly.
Maybe have a look at your swappiness setting, but cgroups certainly will allow you to control things as you want. See the kernel source tree for the best doco.