What is Monitoring and managing Linux process

 

Subject: Linux Administrator                                                      Exp No.   8

 

Aim of the Experiment:  To monitoring and managing Linux process

 

 

Software Required:

1.     VMware

2.     Rhel 7.0

 

 

 

Theory:   

Process: A process is nothing but, a running instance of a launched, executable program. Process has life that’s why it needs resources.  Like files, cpu, resister, stack ,PC, webcam, Printer etc…

Program: It is a set of instruction, written in a programming language and saved in a file. Programs are written to solve real time problem. Program is in-active (passive) in nature that’s why it has no life. It does not need any resources.  

 

• Foreground Processes: They run on the screen and need input from the user.
• Background Processes: They run in the background and usually do not need user input.

 

Implementation/Steps:

             Suppose, I am playing a music with banshee player             #banshee

            To stop the running command,   press                                   #(ctrl+z)

            To continue it and take it in foreground                                 #fg banshee

            To see all running process on the Linux machine                  #top

                                   

                                    It will appear something like this:

            To move out of the process display:                          press  ‘q’

Terminologies: -

Field	Description	Example 1	Example 2
PID	The process ID of each task	2952	6219
User	The username of task owner	root	root
PR	Priority Can be 20(highest) or -20(lowest)	20	20
NI	The nice value of a task	0	0
VIRT	Virtual memory used (kb)	1707420	123924
RES	Physical memory used (kb)	244988	1924
SHR	Shared memory used (kb)	39056	1152
S	Status There are five types: ‘D’ = uninterruptible sleep ‘R’ = running ‘S’ = sleeping ‘T’ = traced or stopped ‘Z’ = zombie	S	R
%CPU	% of CPU time	3.3	0.7
%MEM	Physical memory used	6.3	0.0
TIME+	Total CPU time	2:53.42	0:00.0.6
Command	Command name	Gnome-shell	top

           

 

                        To check all the processes running under a user                    #ps ux

                        To check process status of a single process                           #ps 1268

                         To terminate a running process                                             kill 1268

                        To know the PID of a command (Xorg)                                #pidof Xorg

                        To terminate/kill all running process                                     #killall

                       

NICE

Linux can run a lot of processes at a time, which can slow down the speed of some high priority processes and result in poor performance. To tell our machine to prioritize processes as per our requirements.

nice has a value between -20 to 19. The lower the Niceness index, the higher would be a priority given to that task.

The default value of all the processes is 0.

 

To renice the value                                                     #renice 20-p 2952

                                                                        #renice ‘nice value’ –p ‘PID’

To check the free disk space on all file system          #df

To see free disk space in readable form                     #df –h

 

 

 

 

 

 

 

 

 

 

 

 

 

Conclusion:

In this experiment I know about process, fore-ground, back-ground process, about job of the processes, to kill the running process, to renice the processes, and to see the storage etc.

 

                                                                                                 

 

                                                                                                

 

 

 

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