identify perf's PID using top/ps - linux

I need to kill perf in a bash script using its PID. However, unable to identify perf's PID (using top). Any pointers appreciated. Ubuntu XX 16.04.2. Thanks.

You can grep ps for the process and get its id from there. then use the output from that with your kill command.
kill $(ps aux | awk '/perf/{print $2}')

Related

How to extract a column value from a command output in shell script

I am trying to write a shell script where I want to kill a list of processes given by fuser command.
The output of fuser is given. I want to kill the pids listed
kill -9 157909 1504107 1504111 1504112 2690311 3206490
How do I do that?
-k, --kill
Kill processes accessing the file. Unless changed with -SIGNAL,
SIGKILL is sent. An fuser process never kills itself, but may
kill other fuser processes. The effective user ID of the
process executing fuser is set to its real user ID before
attempting to kill.
fuser -k will do it.
ps -u beadm | awk '{print $2}' | while read line; do kill -9 $line; done

how to use kill command only with files name without PID

I wanna kill programs with one command
ps -elf | grep "common_program_name" | grep -v grep | awk '{print $2}' | xargs kill -9
but I got an error
kill: failed to parse argument: 'S
what am I doing wrong ?
Use killall -9 common_program_name
the problem above is that you might have more than one instance of the program running.
Also, you are fetching the second column from the output of ps That column does not contain a PID, so your xargs command effectively runs kill -9 S Perhaps you can adjust your flags to ps or your field captured by awk to make the above work, but there are already purpose built programs which do this job.
Use pkill, in your case pkill -9 common_program_name (for more see man pkill) which gives you the functionality you're looking for. And unlike killall won't kill literally all process on System V UNIX machines. ;)

how can I kill a process in a shell script

My bash script has:
ps aux | grep foo.jar | grep -v grep | awk '{print $2}' | xargs kill
However, I get the following when running:
usage: kill [ -s signal | -p ] [ -a ] pid ...
kill -l [ signal ]
Any ideas, how to fix this line?
In general, your command is correct. If a foo.jar process is running, its PID will be passed to kill and (should) terminate.
Since you're getting kill's usage as output, it means you're actually calling kill with no arguments (try just running kill on its own, you'll see the same message). That means that there's no output in the pipeline actually reaching xargs, which in turn means foo.jar is not running.
Try running ps aux | grep foo.jar | grep -v grep and see if you're actually seeing results.
As much as you may enjoy a half dozen pipes in your commands, you may want to look at the pkill command!
DESCRIPTION
The pkill command searches the process table on the running system and signals all processes that match the criteria
given on the command line.
i.e.
pkill foo.jar
Untested and a guess at best (be careful)
kill -9 $(ps -aux | grep foo.jar | grep -v grep | awk '{print $2}')
I re-iterate UNTESTED as I'm not at work and have no access to putty or Unix.
My theory is to send the kill -9 command and get the process id from a sub shell command call.

Given a PPID, how to find all of associated PID?

It might be a weird question as I searched and found many people asking about how to find the PPID given a PID. However, I'm interested in finding out all the PID of a given PPID.
The incentive was to run a process check using pidstat and from my test with pidstat, it seems to be that pidstat only reports meaningful child process stats and if I have a driver script and I want to access each individual processes within the driver script, I need to htop and find out the PIDs individually. When I invoked a driver script, such as bash script.sh, there is a ID associated with this command and this ID becames the PPID of all the processes within the driver scripts (if I understand it correctly).
So does anyone know how to get all the PIDs of a PPID?
Thanks!
Use pgrep. man pgrep for usage.
pgrep -P <ppid>
Try doing this :
$ ps --ppid <YOUR PPID> -o pid=
$ ps -x -o pid,ppid | grep -E '[^0-9]{Enter PPID HERE}$' # on Mac OS Terminal
.
e.g. if ppid = 1
$ ps -x -o pid,ppid | grep -E '[^0-9]1$' # on Mac OS Terminal

How can I kill a process by name instead of PID, on Linux? [duplicate]

This question already has answers here:
Find and kill a process in one line using bash and regex
(30 answers)
Closed 1 year ago.
Sometimes when I try to start Firefox it says "a Firefox process is already running". So I have to do this:
jeremy#jeremy-desktop:~$ ps aux | grep firefox
jeremy 7451 25.0 27.4 170536 65680 ? Sl 22:39 1:18 /usr/lib/firefox-3.0.1/firefox
jeremy 7578 0.0 0.3 3004 768 pts/0 S+ 22:44 0:00 grep firefox
jeremy#jeremy-desktop:~$ kill 7451
What I'd like is a command that would do all that for me. It would take an input string and grep for it (or whatever) in the list of processes, and would kill all the processes in the output:
jeremy#jeremy-desktop:~$ killbyname firefox
I tried doing it in PHP but exec('ps aux') seems to only show processes that have been executed with exec() in the PHP script itself (so the only process it shows is itself.)
pkill firefox
More information: http://linux.about.com/library/cmd/blcmdl1_pkill.htm
Also possible to use:
pkill -f "Process name"
For me, it worked up perfectly. It was what I have been looking for.
pkill doesn't work with name without the flag.
When -f is set, the full command line is used for pattern matching.
You can kill processes by name with killall <name>
killall sends a signal to all
processes running any of the specified
commands. If no signal name is
specified, SIGTERM is sent.
Signals can be specified either by
name (e.g. -HUP or -SIGHUP ) or by number (e.g.
-1) or by option -s.
If the command name is not regular
expression (option -r) and contains a
slash (/), processes executing that
particular file will be selected for
killing, independent of their name.
But if you don't see the process with ps aux, you probably won't have the right to kill it ...
A bit longer alternative:
kill `pidof firefox`
The easiest way to do is first check you are getting right process IDs with:
pgrep -f [part_of_a_command]
If the result is as expected. Go with:
pkill -f [part_of_a_command]
If processes get stuck and are unable to accomplish the request you can use kill.
kill -9 $(pgrep -f [part_of_a_command])
If you want to be on the safe side and only terminate processes that you initially started add -u along with your username
pkill -f [part_of_a_command] -u [username]
Kill all processes having snippet in startup path. You can kill all apps started from some directory by for putting /directory/ as a snippet. This is quite usefull when you start several components for the same application from the same app directory.
ps ax | grep <snippet> | grep -v grep | awk '{print $1}' | xargs kill
* I would prefer pgrep if available
Strange, but I haven't seen the solution like this:
kill -9 `pidof firefox`
it can also kill multiple processes (multiple pids) like:
kill -9 `pgrep firefox`
I prefer pidof since it has single line output:
> pgrep firefox
6316
6565
> pidof firefox
6565 6316
Using killall command:
killall processname
Use -9 or -KILL to forcefully kill the program (the options are similar to the kill command).
On Mac I could not find the pgrep and pkill neither was killall working so wrote a simple one liner script:-
export pid=`ps | grep process_name | awk 'NR==1{print $1}' | cut -d' ' -f1`;kill $pid
If there's an easier way of doing this then please share.
To kill with grep:
kill -9 `pgrep myprocess`
more correct would be:
export pid=`ps aux | grep process_name | awk 'NR==1{print $2}' | cut -d' ' -f1`;kill -9 $pid
I normally use the killall command.
Check this link for details of this command.
I was asking myself the same question but the problem with the current answers is that they don't safe check the processes to be killed so... it could lead to terrible mistakes :)... especially if several processes matches the pattern.
As a disclaimer, I'm not a sh pro and there is certainly room for improvement.
So I wrote a little sh script :
#!/bin/sh
killables=$(ps aux | grep $1 | grep -v mykill | grep -v grep)
if [ ! "${killables}" = "" ]
then
echo "You are going to kill some process:"
echo "${killables}"
else
echo "No process with the pattern $1 found."
return
fi
echo -n "Is it ok?(Y/N)"
read input
if [ "$input" = "Y" ]
then
for pid in $(echo "${killables}" | awk '{print $2}')
do
echo killing $pid "..."
kill $pid
echo $pid killed
done
fi
kill -9 $(ps aux | grep -e myprocessname| awk '{ print $2 }')
If you run GNOME, you can use the system monitor (System->Administration->System Monitor) to kill processes as you would under Windows. KDE will have something similar.
The default kill command accepts command names as an alternative to PID. See kill (1). An often occurring trouble is that bash provides its own kill which accepts job numbers, like kill %1, but not command names. This hinders the default command. If the former functionality is more useful to you than the latter, you can disable the bash version by calling
enable -n kill
For more info see kill and enable entries in bash (1).
ps aux | grep processname | cut -d' ' -f7 | xargs kill -9 $
awk oneliner, which parses the header of ps output, so you don't need to care about column numbers (but column names). Support regex. For example, to kill all processes, which executable name (without path) contains word "firefox" try
ps -fe | awk 'NR==1{for (i=1; i<=NF; i++) {if ($i=="COMMAND") Ncmd=i; else if ($i=="PID") Npid=i} if (!Ncmd || !Npid) {print "wrong or no header" > "/dev/stderr"; exit} }$Ncmd~"/"name"$"{print "killing "$Ncmd" with PID " $Npid; system("kill "$Npid)}' name=.*firefox.*

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