L9 Study Guide Questions - Managing Linux Processes

A foreground process can be paused with Ctrl+z combination and sent to the background with the __________ command.

(bg) background

After a background process has been started, the ______________command moves this background process to the foreground.

(fg) foreground

ps =

(process state) looks at the processes that are running

A ____________user process______________ is a process begun by a user on a terminal.

...

A __________deamon process____________ is a system process that is not associated with a terminal.

...

Each process can start an unlimited number of other processes. These new processes are called __________child processes________________.

...

Each process must be started by an existing process. This existing process is called a __________parent processes________________.

...

Every process has a unique __________process ID________________ that allows the kernel to identify it uniquely.

...

he most recent background processes with a + symbol and the second most recent background processes with a - symbol.

...

The ________________________ is a file listing all of the users that are able to use the at command.

/etc/at.allow

The _______________________ is a file listing all of the users that are not able to use the at command.

/etc/at.deny

The _______________________ file lists all of the users that are able to use the cron command.

/etc/cron.allow

The _____________________ file lists all of the users that are not able to access the cron command.

/etc/cron.deny

The system cron tables contain system tasks and exist in the ____________________ file as well as in the /etc/cron.d directory.

/etc/crontab

The at daemon uses the current shell's environment when executing scheduled commands. The shell environment and scheduled commands are stored in the ___________ directory.

/var/spool/at

By default, a process starts with a NI value of _________________________.

0

the default value for time priority is _______

0

A foreground process can be paused with ________combination

Ctrl+z

The ________________ daemon is a system daemon that executes tasks once at a future time.

at

The _____________________ command is used to view the contents of the shell environment at the time the at job was schedul

at -c

The ________________________ command is used to delete a scheduled job.

at -d

The _______________________ command is used to run scheduled jobs from a shell script.

at -f

The _____________________ command is used to view a list of scheduled jobs

at -l

___________ processes are processes that the BASH shell does not wait for termination. It uses the & metacharacter as part of the command and the user receives the BASH shell prompt immediately.

background

System maintenance, backups, and CPU-intensive tasks are often scheduled during non-business hours and are often scheduled by the _______________________ daemon

cron

The _________________ daemon is a system daemon that executes tasks repetitively in the future

cron

___________________ are configuration files specifying tasks for the cron daemon to run. In the cron tables, the commands to be executed should be specified.

cron tables

The ______________________ command lists a user's cron table.

crontab - l

The ______________________ command removes a cron table and all scheduled jobs.

crontab - r

The PRI is _______________ related to the amount of time slices a process has on the CPU

directly

e =

entire

________ __ processes are processes that the BASH shell must wait for termination

foreground

___________ is an act of creating a new BASH shell and it is carried out with the fork function in the BASH shell.

forking

- f =

full option

A negative nice value ________________ the likelihood that the process will receive more time slices, whereas a positive nice value does the opposite.

increases

Although the system administrator cannot change the PRI value directly, the nice (NI) value can be set to _____________ affect the priority of a process

indirectly

The first process started by the Linux kernel is the _____________________ daemon, which has a PID of 1 and a PPID of 0 referring to the kernel itself.

inti

The ___________________ command lists all background processes running in the current shell.

jobs

When there are multiple background processes executing in the shell, the ____________________ command indicates the most recent background processes with a + symbol and the second most recent background processes with a - symbol.

jobs

A ______________ command is the most common command used to terminate a process. It sends a kill signal to the process.

kill

when you kill off the parent process you.......

kill of the child processes

The _________________ command kills all instances of a process by the command name. It uses the process name instead of its PID.

killall

The ______________________ command changes a process's priority as it starts

nice

The ________________ can be used to affect the process priority indirectly. It is measured between - 20 (a greater chance of a high priority) and 19 (a greater chance of a lower priority

nice value (NI)

As a result, each process has a ______________________, which identifies the process that started it.

parent process ID (PPID)

A _________________________ is a program that is running in memory and on the CPU.

process

_______________________ is the priority used by the kernel for the process. It is measured between 0 (high priority) and 127 (low priority).

process priorities (PRI)

The ____________________ indicates what the process is currently doing. Most processes are either sleeping (S) or running (R).

process state

A _______________________ is an executable file on the hard disk that can be run when you execute it.

program_

Without arguments, the ________________________ command simply displays a list of processes that are running in the current shell. It includes the PID, terminal, CPU time and the command that started the process.

ps

The ____________________ command displays the lineage of a process by tracing its PPIDs until the init daemon.

pstree

The _________________ command will alter the NI of a process after it is running.

renice

A ______________is a faulty process that consumes an excessive amount of system resources.

rogue process

A _______________ is an amount of time a process has to use the CPU on a multiprocessing operating system.

time slice

The ______________________ utility can also be used to change the NI value of running processes.

top

The ________________________ command displays an interactive screen listing processes organized by processor time. Processes that use the most processor time are listed at the top of the screen.

top

A PRI of 0 is the most likely to get time slices on the CPU and a PRI of 127 is the least likely to receive time slices on the CPU. true or false????

true

On a busy Linux server, zombie processes can accumulate and prevent new processes from being created. If this occurs, you can simply kill the parent process of the zombies. true or false???

true

Only the root user may change NI to a negative value using the renice command. true or false???

true

The ps command is not the only command that can display process information. true or false???

true

While a process is waiting for its parent process to release the PID, the process is said to be in a ____________________ state, because it has finished but retains a PID.

zombie

The only kill signal that cannot be trapped by any process is the __________.

SIGKILL 9

If you do not specify the kill signal when using the kill command, the kill command uses the default kill signal which is ____________.

SIGTERM (15)