Week 5 - Life of a Process Flashcards
What are processes given to identify it from other processes?
A process ID
What are background processes? What are they also called?
Background processes run in the background (unlike processes in the foreground)
Also called daemon processes
What is the session manager subsystem?
Windows
The first non-kernel/user mode process that loads up on Windows Boot. It prepares the OS.
smss.exe
What is the Windows logon software kicked off by the smss.exe?
Windows
windlogon.exe
What is also kicked off first by the smss.exe besides Windows logon software? What does this software handle?
Client Server Runtime Subsystem, handles the GUI and command line console
csrss.exe
The way processes are created and stopped differ based on ____
the OS
What is the first process Linux uses?
init
When a child process inherits __, __ from its parent, what is that called?
settings, variables are inherited
it’s then called an environment
How do child/parent processes differ in Linux and Windows?
In Windows, child processes can run independently from their parent
With what command do you stop a process in Windows?
taskkill utility
most commonly can use /pid
taskkill /pid ####
What’s the shortcut to open the task manager? Windows
CTRL-SHIFT-ESC
How do you get the PID from the task manager GUI? Windows
Details tab
2 ways to show all running processes in Windows through commands?
- tasklist
- Get-Process
3 ways to get the PID of a process? Windows
- Task Manager > Details tab
- tasklist
- Get-Process
How to view running processes on Linux? 2 ways
Explain what the flags mean
- ps -x
- 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
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
ls -l /proc
More info:
cat /proc/PIDnumber/status
What command do you use to search through the process output for a particular process?
Linux
ps -ef | grep Firefox
What does smss.exe stand for?
Session Manager Subsystem
What is a signal?
Windows
A signal is a way to tell a process that something has happened
What does SIGINT stand for?
SIGINT = signal interrupt
How do you send a SIGINT signal to a running process? Windows + Linux
CTRL + C
SIGINT is not supported by which version of Windows?
Windows 32-bit
What is Process Explorer? Windows
A utility provided by Windows used by IT professionals to look at running processes more in-depth
What does MUI stand for?
Multilingual User Interface
Offers multi-language support (found in Process Explorer)
How do you terminate a running process in Linux? 2 ways
- 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)
- kill -KILL PID#
kill command with -KILL SIGKILL signal will overkill terminate process (doesn’t let it clean up resources it was using)
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
It can cause file corruption
What does SIGTERM and SIGTSTP mean?
SIGTERM = signal for terminate
SIGTSTP = signal for terminal stop
What command do you use to see the status of a running process? Linux
ps -x
doesn’t show up with ps -ef
How do you pause/suspend a process in Linux? 3 ways
- kill -TSTP PID#
- CTRL + Z
- CTRL + C
What’s the keyboard shortcut to pause/suspend a process in Linux?
CTRL + Z
What does SIGCONT stand for? Linux
Continued (signal)
With what command do you resume the execution of a process? Linux
kill -CONT PID#
What are 4 troubleshooting tips for mobile app management?
- Close out of background apps one by one to find problem app
- Clear cache of problem app
- Restart device if device is still sluggish after closing all apps
- Check battery usage of apps if restarting device temp solves or doesn’t work
What are the 5 sections of the ps -ef (view running processes) output on Linux?
- PID
- TTY (terminal associated w/ process)
- STAT - status (R, T, S)
- TIME - total CPU time used
- COMMAND - that we’re running
What are 3 things the top command does in Linux
- provides info on process CPU and memory usage
- lists top processes using most resources
- provides snapshot of total tasks running/idling
In iOS and Android, what’s the first thing you should try when troubleshooting a problem app?
close apps, one at a time, starting with foreground app
In the output of the ps -ef command, what are the 3 different status types?
R - Running
S - Sleeping, interruptible (idle)
T - Stopped
In Linux, what process has the PID of 1?
init
What 3 tools can you use to monitor system resources in Windows?
Resource Monitor
Get-Process (PowerShell commandlet)
tasklist
