Setting Resource Limits on Ubuntu
While you can use Warden to automatically set resource limits, you may want to set limits manually.
About this task
Rather than relying on Warden to set resource limits automatically using ulimit, 
                you can use the following procedure to set the limits manually.
Procedure
- 
                Edit 
/etc/security/limits.confand add a line to set the resource limits. For example, set the resource limits:<MAPR_USER> - nofile 65536 <MAPR_USER> - nproc 64000 - 
                Edit 
/etc/pam.d/suand uncomment the following line.session required pam_limits.so - 
                Edit the 
/etc/pam.d/common-session*files to make sure the following entry is present:# end of pam-auth-update config session required pam_limits.so - 
                Use 
ulimitto verify settings. - Reboot the system.
 - 
                Run the following command as the 
mapruser (not root) at a command line:ulimit -n