Configure user resource limits

Any user can change it's own soft limits, between "zero", and the hard limit (typically enforced by pam_limit).

To print all the resource limits for the current user: ulimit -a

Show the current Soft limit for "memlock":

ulimit -S -l
> 64

Set the current Soft "memlock" limit to 48KiB:

ulimit -S -l 48

The system resources are defined in a configuration file located at /etc/security/limits.conf. ulimit, when called, will report these values.

To manually set resource limits for users or groups: sudo vim /etc/security/limits.conf

Each entry has to follow the following structure: [domain] [type] [item] [value].

These are some example lines which might be specified in /etc/security/limits.conf:

*               soft    core            0
root            hard    core            100000
*               hard    rss             10000
@student        hard    nproc           20
@faculty        soft    nproc           20
@faculty        hard    nproc           50
ftp             hard    nproc           0
@student        -       maxlogins       4

To find limits for a process:

cat /proc/<PID>/limits