Week 5 - Life of a Process

Question 1

What are processes given to identify it from other processes?

Answer 1

A process ID

Question 2

What are background processes? What are they also called?

Answer 2

Background processes run in the background (unlike processes in the foreground)

Also called daemon processes

Question 3

What is the session manager subsystem?

Windows

Answer 3

The first non-kernel/user mode process that loads up on Windows Boot. It prepares the OS.

smss.exe

Question 4

What is the Windows logon software kicked off by the smss.exe?

Windows

Answer 4

windlogon.exe

Question 5

What is also kicked off first by the smss.exe besides Windows logon software? What does this software handle?

Answer 5

Client Server Runtime Subsystem, handles the GUI and command line console

csrss.exe

Question 6

The way processes are created and stopped differ based on ____

Answer 6

the OS

Question 7

What is the first process Linux uses?

Answer 7

init

Question 8

When a child process inherits __, __ from its parent, what is that called?

Answer 8

settings, variables are inherited

it’s then called an environment

Question 9

How do child/parent processes differ in Linux and Windows?

Answer 9

In Windows, child processes can run independently from their parent

Question 10

With what command do you stop a process in Windows?

Answer 10

taskkill utility

most commonly can use /pid

taskkill /pid ####

Question 11

What’s the shortcut to open the task manager? Windows

Answer 11

CTRL-SHIFT-ESC

Question 12

How do you get the PID from the task manager GUI? Windows

Answer 12

Details tab

Question 13

2 ways to show all running processes in Windows through commands?

Answer 13

1. tasklist
2. Get-Process

Question 14

3 ways to get the PID of a process? Windows

Answer 14

1. Task Manager > Details tab
2. tasklist
3. Get-Process

Question 15

How to view running processes on Linux? 2 ways

Explain what the flags mean

Answer 15

1. ps -x
2. ps -ef

-x gives you a snapshot of all the processes running
-e gives you everything, all processes, including ones started by other users
-f gives you the full details about a process

Question 16

What command do you use to view files that correspond to processes on Linux? How do you get more detailed information about the status of a process?

2 answers

Answer 16

ls -l /proc

More info:
cat /proc/PIDnumber/status

Question 17

What command do you use to search through the process output for a particular process?
Linux

Answer 17

ps -ef | grep Firefox

Question 18

What does smss.exe stand for?

Answer 18

Session Manager Subsystem

Question 19

What is a signal?
Windows

Answer 19

A signal is a way to tell a process that something has happened

Question 20

What does SIGINT stand for?

Answer 20

SIGINT = signal interrupt

Question 21

How do you send a SIGINT signal to a running process? Windows + Linux

Answer 21

CTRL + C

Question 22

SIGINT is not supported by which version of Windows?

Answer 22

Windows 32-bit

Question 23

What is Process Explorer? Windows

Answer 23

A utility provided by Windows used by IT professionals to look at running processes more in-depth

Question 24

What does MUI stand for?

Answer 24

Multilingual User Interface

Offers multi-language support (found in Process Explorer)

Question 25

How do you terminate a running process in Linux? 2 ways

Answer 25

1. kill PID# kill command without any flags sends a termination signal SIGTERM. Kills process but gives it time to clean up resources it was using (prevents file corruption) 2. kill -KILL PID# kill command with -KILL SIGKILL signal will overkill terminate process (doesn’t let it clean up resources it was using)

Question 26

What happens if you don't let a process clean up the files it was working with? For example, forcefully terminating a process with SIGKILL versus a normal SIGTERM signal

Answer 26

It can cause file corruption

Question 27

What does SIGTERM and SIGTSTP mean?

Answer 27

SIGTERM = signal for terminate SIGTSTP = signal for terminal stop

Question 28

What command do you use to see the status of a running process? Linux

Answer 28

ps -x doesn't show up with ps -ef

Question 29

How do you pause/suspend a process in Linux? 3 ways

Answer 29

1. kill -TSTP PID# 2. CTRL + Z 3. CTRL + C

Question 30

What's the keyboard shortcut to pause/suspend a process in Linux?

Answer 30

CTRL + Z

Question 31

What does SIGCONT stand for? Linux

Answer 31

Continued (signal)

Question 32

With what command do you resume the execution of a process? Linux

Answer 32

kill -CONT PID#

Question 33

What are 4 troubleshooting tips for mobile app management?

Answer 33

1. Close out of background apps one by one to find problem app 2. Clear cache of problem app 3. Restart device if device is still sluggish after closing all apps 4. Check battery usage of apps if restarting device temp solves or doesn't work

Question 34

What are the 5 sections of the ps -ef (view running processes) output on Linux?

Answer 34

1. PID 2. TTY (terminal associated w/ process) 3. STAT - status (R, T, S) 4. TIME - total CPU time used 5. COMMAND - that we're running

Question 35

What are 3 things the top command does in Linux

Answer 35

1. provides info on process CPU and memory usage 2. lists top processes using most resources 3. provides snapshot of total tasks running/idling

Question 36

In iOS and Android, what's the first thing you should try when troubleshooting a problem app?

Answer 36

close apps, one at a time, starting with foreground app

Question 37

In the output of the ps -ef command, what are the 3 different status types?

Answer 37

R - Running S - Sleeping, interruptible (idle) T - Stopped

Question 38

In Linux, what process has the PID of 1?

Answer 38

init

Question 39

What 3 tools can you use to monitor system resources in Windows?

Answer 39

Resource Monitor Get-Process (PowerShell commandlet) tasklist