Sec. 12 Process Monitoring

Question 1

top

Answer 1

process activity dynamically updated

Question 2

uptime

Answer 2

how long the system is running and teh average load.

Question 3

ps

Answer 3

detailed information about processes

Question 4

pstree

Answer 4

a tree of processes

Question 5

mpstat

Answer 5

multiple processor usage

Question 6

iostat

Answer 6

CPU utilization and I/O statistics

Question 7

sar

Answer 7

display and collect information about system activity

Question 8

numastat

Answer 8

information about NUMA ( non-uniform memory architecture)

Question 9

strace

Answer 9

information about all system calls a process makes

Question 10

what filesystem can be helpful in monitoring processes ?

Answer 10

/proc filesystem

Question 11

ps is a ____________ for displaying characteristics and statistics associated with processes.

Answer 11

ps is a workhorse for displaying characteristics and statistics associated with processes.

Question 12

VSZ in the ps output

Answer 12

VSZ stands for the process’ virtual memory size in KB

Question 13

RSS in the ps output

Answer 13

RSS stand for the resident set size; the non-swapped physical memory a task is using in KB

Question 14

STAT output for the ps command

Answer 14

the STAT area describes the state of the process;

• < for high prority (not nice)
• S stands for sleeping
• R stands for running
• N for low priority (nice)
• L for having pages locked in memory
• s for session leader
• l for multi-threaded
• + for being in the forground process group

Question 15

-o options for the ps command followed by a comma seperated list of field identifiers, I can print out a …….?

Answer 15

-o options for the ps command followed by a comma seperated list of field identifiers, I can print out a customized list of ps fields .

• ps fields:
  
  • ​pid: process ID number
  • uid: user ID number
  • cmd: command with all arguments
  • cputime: cumulative CPU time
  • pmem: Ratio of teh process’s resident set size to the physical memory on the machine, expressed as a percentage.

Question 16

ps field: pid

Answer 16

process ID number

Question 17

ps -A or ps -e

Answer 17

select all processes

Question 18

if the -o option is specified, followed by a _____________ list of field identifiers , you can print a customized list of ps fields.

Answer 18

comma-seperated

Question 19

process states: D

Answer 19

uninterruptible sleep

Question 20

process state: I

Answer 20

Idle kernel thread

Question 21

process state: R

Answer 21

running or runnable (on run queue)

Question 22

process state: S

Answer 22

interruptible sleep( waiting for event to complete)

Question 23

process state: T

Answer 23

stopped by debugger during the tracing

Question 24

process state: t

Answer 24

stopped by debugger during the tracing

Question 25

process state: Z

Answer 25

defunct (“zombie”) process terminated but not reaped by its parent.

Question 26

ps works by reading the virtual files in ______?

Answer 26

/proc

Question 27

ps field : uid

Answer 27

user id number

Question 28

ps field : cmd

Answer 28

command with all arguements

Question 29

ps field : cputime

Answer 29

cumulative cpu time

Question 30

ps field : pmem

Answer 30

ratio of the process’s resident set size to the physical memory on the machine

Question 31

ps