System Always has a process sleep under root user. Accidentally found this. It sleeps for 60 seconds, then start again. Always there. I'm using CENTOS. root 8251 0.0 0.0 107948 348 ? S 12:10 0:00 sleep 60 Thought it suspicious. Found this by `ps axlfww`: 1 0 1541 1 20 0 115300 988 do_wai S ? 0:01 /bin/bash /usr/sbin/ksmtuned 0 0 15266 1541 20 0 107948 344 hrtime S ? 0:00 \_ sleep 60 Looks it's related to SELinux, so probably ok. https://linux.die.net/man/8/ksmtuned_selinux