ps is a command for printing information about running processes

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How can I prevent 'grep' from showing up in ps results?

When I search for some process that doesn't exist, e.g. $ ps aux | grep fnord wayne 15745 0.0 0.0 13580 928 pts/6 S+ 03:58 0:00 grep fnord Obviously I ...
60
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2answers
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Why does `htop` show more process than `ps`

In ps xf 26395 pts/78 Ss 0:00 \_ bash 27016 pts/78 Sl+ 0:04 | \_ unicorn_rails master -c config/unicorn.rb 27042 pts/78 Sl+ 0:00 | ...
58
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4answers
8k views

In what order do piped commands run?

I've never really thought about how the shell actually executes piped commands. I've always been told that the "stdout of one program gets piped into the stdin of another," as a way of thinking about ...
45
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5answers
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How can I get a full process list in solaris, without truncated lines?

Is there a way to generate a full process listing in solaris, without truncated lines? I've tried the ps command, with the following arguments: -f Generates a full listing. ...
42
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3answers
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What are “session leaders” in `ps`?

What are session leaders, as in ps -d which selects all processes except session leaders?
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2answers
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What does aux mean in `ps aux`?

ps aux seems to conveniently list all processes and their status and resource usage (Linux/BSD/MacOS), however I cannot comprehend the meaning of parameter aux using man ps. What does aux mean?
36
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2answers
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What do the brackets around processes mean?

mark@mark-VirtualBox:~/auto/lib$ ps -Awwo pid,comm,args PID COMMAND COMMAND 1 init /sbin/init 2 kthreadd [kthreadd] 3 ksoftirqd/0 [ksoftirqd/0] 5 ...
33
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9answers
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Show top five CPU consuming processes with `ps`

How to show top five CPU consuming processes with ps?
30
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1answer
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How to see process created by specific user in Unix/linux

I want to see list of process created by specific user or group of user in Linux Can I do it using ps command or is there any other command to achieve this?
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2answers
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Top and ps not showing the same cpu result

This is linked to this question. When I run top I get the following result: pid 3038 is using 18% cpu, however when running the result is 5.5%. And this number does not appear to be changing ...
24
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2answers
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When was a process started

To know when was a process started, my first guess was to check the time when /proc/<pid>/cmdline was written/modified the last time. ps also shows a START field. I thought both of these ...
21
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6answers
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Can ps display only non kernel processes on Linux?

How can I ask ps to display only user processes and not kernel threads? See this question to see what I mean...
16
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1answer
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What does this process STAT indicates?

If you check the STAT column in above image you will see Ss S S< SN and R+ What does this indicates ? Process states. If yes,Then what is the significance of 'Ss S< SN and R+'?
16
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3answers
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What would cause ps to report uid instead of username?

I have Eucalyptus installed on my Linux machine, and I've noticed that for processes owned by the eucalyptus user, ps reports the userid instead of the username. For example: $ sudo -i -u eucalyptus ...
16
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2answers
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How does ps know to hide passwords?

Witness: $ ps f PID TTY STAT TIME COMMAND 31509 pts/3 Ss 0:01 -bash 27266 pts/3 S+ 0:00 \_ mysql -uroot -p 25210 pts/10 Ss+ 0:00 /bin/bash 24444 pts/4 Ss 0:00 ...
14
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3answers
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Elegantly get list of descendant processes

I would like to get a list of all the processes that descend (e.g. children, grand-children, etc) from $pid. This is the simplest way I've come up with: pstree -p $pid | tr "\n" " " |sed "s/[^0-9]/ ...
13
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5answers
648 views

How to get the tty in which bash is running?

In the second method proposed by this page, one gets the tty in which bash is being run with the command: ps ax | grep $$ | awk '{ print $2 }' I though to myself that surely this is a bit lazy, ...
13
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2answers
985 views

Which to choose - BSD or Unix-style commands where available?

Commands like ps come with a lot of parameters, especially because they give the use an option to choose between Unix and BSD style flags. I hope you get my point here. So, when there's such an ...
12
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3answers
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ps: full command is too long

Good day! I use 'ps' to see command that starts process. The issue is that command is too long and 'ps' does not show it entirely. Example: I use command 'ps -p 2755 | less' and have following ...
10
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6answers
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How to extract a key value pair from ps command

I am trying to extract application name from ps command: ps -af -u sas |grep "java"| grep -v "grep" above command produces the following: sas 24431 1 0 Oct10 ? 00:51:08 ...
10
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2answers
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ps switches to display PID, PPID, PGID, and SID collectively

I tried ps with different kinds of switches e.g. -A, aux, ef, and so forth but I cannot seem to find the right combination of switches that will tell me the Process ID (PID), Parent Process ID (PPID), ...
9
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1answer
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Elegantly get list of children processes

I would like to get a list of all the processes whose parent is $pid. This is the simplest way I've come up with: pstree -p $pid | tr "\n" " " |sed "s/[^0-9]/ /g" |sed "s/\s\s*/ /g" Is there any ...
9
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1answer
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Why the value of VSIZE in top is different from the value of VSZ (Virtual set size) in ps?

I know VSZ in ps is for the total address space allocated for the app and is sometimes aliased as vsize (mentioned in man page of ps on linux), but what's the definition of VSIZE in top? This top ...
8
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3answers
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How is it possible to sort ps command's CPU field?

I'm trying to make a small command that will find the processes that use the most CPU power. Firstly, I use ps aux > file.txt and then cut -c 16-20 file.txt | sort -n | tail -5. The result I get ...
8
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3answers
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What does the “interruptible sleep” state indicate?

I had Firefox running on a Parted Magic LiveCD, then (possibly) as a result of a key combination I don't recall, it quickly vanished from screen and Task Bar/Window List. However: ps ax | grep ...
8
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1answer
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Why does “kill -9 0” end my console session?

I just wonder why kill -9 0 ends my tty console session? What exactly is PID 0, it is not listed on a ps aux?
8
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3answers
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Format cputime for ps

I'm trying to write a script that can monitor a process's CPU usage over an interval (to create a graph). So far, this is the command I'm using ps -p $PROCID -o cputime,etimes My only concern is ...
8
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2answers
242 views

Look for a process with a given name

I am trying to convert the VMS command show/system/process=processname into an equivalent Linux command. I tried the following but it returned none of the processes: ps -C /exeimages/processname.pl ...
7
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2answers
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grep - why do brackets in grep pattern remove the grep process from ps results?

Why do brackets in a grep pattern remove the grep process from ps results? $ ps -ef | grep XXXX [...] XXXX [...] grep XXXX $ ps -ef | grep [X]XXX [...] XXXX
7
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3answers
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Terminating a bash shell script running in the background

I often use bash shell scripts to run simple commands for many different files. For example, suppose that I have the following bash shell script, called script.sh, that runs the program/command foo ...
7
votes
4answers
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Solaris ptree style tool for Linux

I'm looking for the Linux tool that will print the same output as the Solaris ptree. For example: # ptree 538 538 /usr/lib/ssh/sshd 889 /usr/lib/ssh/sshd 890 /usr/lib/ssh/sshd 1498 ...
7
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3answers
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If I see a process running using ps, how can I find the executable?

If I can see a process running using ps -e, how can I find the file which launched it?
7
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1answer
6k views

What does <defunct> mean in the output of ps?

I had issued the ps -ef|grep java command and this is one of the entries that I got : subhrcho 875 803 0 Jan23 pts/5 00:02:27 [java] <defunct> What is <defunct> implying here ? ...
6
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4answers
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Finding the ID of a process and killing it

When ever I need to kill a background process I do ps -e | grep <process_name> Which prints something like this 1766 ? 00:00:13 conky , Then I use the process ID to kill it like so kill 1766 . ...
6
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3answers
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killall gives me `no process found ` but ps

Could somebody explain to me the difference between kill and killall? Why doesn't killall see what ps shows? # ps aux |grep db2 root 1123 0.0 0.8 841300 33956 pts/1 Sl 11:48 0:00 ...
6
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4answers
676 views

list graphical processes from terminal

Do no confuse the question here with how to list processes graphically, that is not what I am asking. In the Terminal, how can i see which processes have a GUI? as in things like firefox, vlc, ...
6
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2answers
1k views

Difference between free -m and ps -euf

I'm not an expert on linux so I do apologize in advance for the silly question. I have a vps machine with ubuntu 10.04 and 512Mb of RAM. I'm trying to guess how much memory is available after running ...
6
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3answers
1k views

Is there a way to select by several conditions in `ps`?

It seems I am missing something blindingly obvious, but still: ps -f -u myuser --ppid 1 Seems to only take a look at parent pid of the process, and returns all the processes that have parent pid of ...
6
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1answer
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Mathematical connection between SZ RSS and VSZ in ps o/p?

I wanted to know what mathematical connection is there between the SZ, RSS and VSZ output in ps output e.g. ps -p 2363 -o sz,rss,vsz
6
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3answers
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What's the best way to determine the working directory for UNIX process using 'ps'?

I am running a Ruby command line script (rufus.sh)which ultimately calls Thread.new, which spawns a UNIX process as shown below. I run this script for more than 1 directory as the output of the ps ...
6
votes
1answer
256 views

What is the meaning of this test expression []? [duplicate]

I've seen someone use command: ps -ef | grep [h]ttpd and Output is: apache 25125 31006 0 21:54 ? 00:00:00 /usr/sbin/httpd apache 26869 31006 0 22:04 ? 00:00:00 ...
5
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5answers
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Piping PS output into a Text file

So what im wanting to do is pretty basic.....but im not sure how to go about it. Lets say I have a program running, but I want to pipe the output of ps -C "ProgramXX" into a file. Normally Running ps ...
5
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1answer
366 views

Why does “cat /tmp/out1 > /tmp/in2 &” appear as “bash” with the “ps” command?

Consider: mkfifo /tmp/out1 mkfifo /tmp/in2 cat /tmp/out1 > /tmp/in2 & When I run ps it appears as bash in the CMD section. Why?
5
votes
3answers
6k views

How to get whole command line from a process?

How can I get the command arguments or the whole command line from a running process using its process name? For example this process: # ps PID USER TIME COMMAND 1452 root 0:00 ...
5
votes
1answer
142 views

Find all users who have more than N processes and echo them in shell

I'm writing a script in ksh. I need to find all users who have more than N processes and echo them in the shell. N is read from ksh. I know that I should use ps -elf, but how do I parse it, find ...
5
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1answer
640 views

init: is it a user thread or a kernel thread?

init is the first task executed after kernel is loaded, right? Then who is its owner. also I can see [swapper/0] [swapper/1] ..... [swapper/7] having pid 0 PID PPID CPU TASK ST %MEM ...
5
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1answer
481 views

What does `init [2]` mean in the COMMAND column of ps?

Reading What do the brackets around processes mean? I understand that the executable name is printed. Linux ps man page: Sometimes the process args will be unavailable; when this happens, ps will ...
5
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1answer
10k views

Understanding ps elapsed time format for long running processes

I'm using a ps command as part of an exercise to identify processes running longer than a given threshold. I'm using the following template to get the elapsed time for a know process command: ps -eo ...
5
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1answer
3k views

Difference between poll_s and ep_poll WCHAN in ps output

When I issue ps -elf|grep python for example on my system, I see these: 1 S 1000 6020 6008 0 80 0 - 9914 poll_s Jul12 ? 00:00:01 python manage.py run_gunicorn -t 3600 -w 8 -b ...
5
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1answer
13k views

Among “ps” command output fields, %CPU isn't the actual CPU usage of the process?

For example, one of the output fields of this BSD style command, ps aux, is "%CPU". The alternative command, ps -efl outputs the "C" (or CP) field. As per the ps man page: %CPU is the cpu ...