# Day 13 #90DaysOFDevops

For day 13, i dived into the world of process management on linux. A linux system has hundreds or maybe even thousands of processes running simultaneously.

i learnt how to view processes by using the *ps* & *ps aux* command. The *ps* command doesn’t provide much information. When ran without any options it lists the processes started by the currently logged user. This feature isn’t good enough and thats where the *ps aux* command comes in.

When ran, the *ps aux* command will show all the processes running on the sytem for all users. The first process is usually *init* while the last process is the command ran to display, *ps aux*.

They are several processes that use the most resources on a sytem. To view these resource-hungry resources, the *top* command is deployed. This brings out all the processes ordered by resources used, starting with the largest.

Now the priority of a process can be changed by using the *nice* command.The values range from -20 to +19 with zero the deafault value. A high *nice* value means low priority and a low *nice* value means high priority. By the way, there is also a *renice* command. The commands are slightly different and can be confusing. The *nice* command requires you increase the nice value while the *renice* command wants an absolute value for niceness. e.g *nice -n -10 /bin/newfile* increases the nice value by -10,increasing its priority and allocating more resources. *renice 20 6666(PID of the file)* sets the absolute value to 20.

Lastly, i learnt how to schedule processes using the *at* command.

Managing processes is a very important skill for every linux user. I tried my hands on everything stated above and also killed resource-hungry processes. Side note: i finally got around using a text editor while working on the terminal. i learnt how to use *nano*.

Cheers to day 13 and cheers to many more days!