A process is an instance of a computer program that is being executed.

learn more… | top users | synonyms (1)

1
vote
0answers
86 views

pkill -P $ID working while kill — -$ID not

I was playing around with creating and killing process groups on linux ( ubuntu ) I am trying to kill a process group and am being driven crazy by the fact that pkill -P $ID works while kill -- -$ID ...
1
vote
1answer
96 views

Process id of a command ran by an user

Consider i am running just some basic command.. ls Now would the above command have a pid, when it was getting executed? If yes, then how can i determine that pid? when i try echo $! right ...
3
votes
1answer
83 views

Retrieve X11 window ID of a just-launched GUI-program

I want to retrieve the X id of GUI programs I launch in background, in order to work on their windows properties. I've been so far using this workaround: myprogram & sleep 1 winID=$(wmctrl -l | ...
4
votes
3answers
571 views

How can I start a process with any name which does nothing?

I want to start a process that does nothing but is still running. Say I start a process called sadhadxk, and when I run pgrep -x "sadhadxk" I will get the PID number back, like any normal process ...
3
votes
2answers
537 views

Sorting the output of `ps`

I am trying to understand why ps does not behave the way I expect it to. From the man pages, the following command should display ppid and lstart, with items sorted by lstart order. However when I run ...
2
votes
1answer
100 views

Find out to which directory a process is writing?

This question is NOT a duplicate of this question Find out current working directory of a running process?, because the writing directory can be different from the working directory. For example, I ...
2
votes
2answers
123 views

gracefully terminating processes with killall <processname>

I am using several instances (profiles) of Icedove (Thunderbird) and when I need to close all of them, I use: killall icedove According to man killall, if no signal name is specified, SIGTERM is ...
1
vote
2answers
80 views

using sudo create another process

I have wrote a shell script names testShell.I run this shell using command: sudo sh testShell Then I use ps -ef|grep testShell|grep -v grep to check the processes created.I find that system ...
0
votes
1answer
101 views

Pipe stdout to command on stdout

If I had a running process like tail -F watch.txt and I wanted to capture the stdout from this running process and pipe it to another command on stdout how could this be done? Here's an example of a ...
1
vote
1answer
27 views

PID in top different from the $$ one?

I have been always running my following job. #!/bin/sh NO_START=1 STEP_SIZE=1 NO_END=100 DATE_STR=$(date +%m%d_%H%M%S) RUN_DIR=./$DATE_STR mkdir $RUN_DIR echo PID = $$. See $RUN_DIR/$$.log for ...
0
votes
1answer
79 views

command “jobs” cannot see the stopped jobs

I have wrote a very simple shell script to practice command "bg" , "fg" and "jobs": #!/bin/bash myvar=1 while [ $myvar -le 100000000 ] do echo $myvar myvar=$(( $myvar + 1 )) done I use ...
1
vote
1answer
114 views

What is JID (job ID) and is it always smaller than PID? [closed]

I don't know what exactly is JID (job ID) and how it is assigned. What is it's relation to PID and how does one number affect the size of the other in any way?
2
votes
1answer
48 views

How to suspend a process for a certain period of time?

I have several running processes which is started by a shell, but I don't want them to run during 08:00am - 20:00pm for each day because they are really bandwidth-consuming, so , I have to suspend ...
1
vote
0answers
38 views

What does the “k” metric mean in the “sa” output?

From man sa: k cpu-time averaged core usage, in 1k units My questions: How is it calculated? What is the significance?
0
votes
1answer
26 views

Mechanism of multiple call for one script in the same time

Maybe this question is stupid Anyway I have the ruby script which is calling from different places in the same time(with defferent options). Is it safely and how this mechanism realized in linux? I ...
0
votes
1answer
44 views

screen manager with VT100/ANSI terminal emulation

If I join with 'screen' to existing sessions, I can get a list of the sessions with C-a " keystroke and switch between them, however I can't find a way to safely leave/detach and keep all the ...
2
votes
1answer
36 views

list processes running inside of screen (manager with with VT100/ANSI terminal emulation)

I have an application that during installation runs a bunch of processes via screen, so I can see those if attached to the screen, however I don't see those via "ps -ef" or "ps auxww". How can I list ...
0
votes
1answer
42 views

CPU time that accton (psacct) records - recorded time relationship between parent and children processes

I've had 'accton' (in package psacct-6.3.2-63.el6_3.3.x86_64) turned on as I want to be able to report on a particular process (so I've written a script that will take the psacct file and get the ...
0
votes
2answers
92 views

Creating background process and communicating with it

1st thing off, I am really a Linux newbie - knowing just some basics; there's a great chance I didn't know what I need to look for, please redirect me if you know a good source. What I'm trying to do ...
11
votes
4answers
12k views

How to see how many context switches a process makes?

I want to see if my process makes a lot of context switches. I also want to see how manpulating task groups affects the number of context switches.
0
votes
1answer
109 views

How to move a background job from one terminal tab to another? [duplicate]

I have a background job, say jobid 1, in a tab of gnome terminal. Can I move it to a another tab of genome terminal? I understand that the shell process in the first gnome terminal tab is the parent ...
0
votes
0answers
35 views

Why are some processes “killable” by pkill but not killall?

I had over 20 instances of httpd (apache) processes running, so I decided to shutdown these. Normally I use killall, But when I typed killall httpd it just said: No matching processes belonging to ...
0
votes
1answer
910 views

grep for specific process in ps but not the grep command itself [duplicate]

If I want to check if something is running, I do ps aux | grep flamethrower, expecting just to show the processes containing flamethrower in the name. This will always find at least one process, as ...
0
votes
1answer
105 views

Why kernel threads are treated as processes

In output of the ps command like the one below (kthreadd,ksoftirqd,kworker) , i can see that there are some processes that don't have an executable file and i find out that's because they are kernel ...
1
vote
4answers
26k views

Show running processes with file name(s)?

I am using putty to connect my linux server which my sites are in. I can run # ps aux | less to show running processes. But I want to display which files running these processes ? I have also ...
0
votes
3answers
566 views

Find the parent of a process

I am trying to write a script to help with computer security. I am trying to look for open ports, find the PID, and find what called it. I have it working, where my output looks something like this: ...
0
votes
0answers
271 views

System CPU Time and User CPU Time Calculation for a Process in Linux

I want to calculate CPU time consumption of a particular process in system mode and user mode using statistics present in /proc/<PID>. There are two fields utime and stime in ...
2
votes
1answer
1k views

Why does't stopping the nginx server kill the processes associated with it?

When I stop nginx like this on ubuntu 12.04, I get the following errors: $ sudo service nginx stop Stopping nginx: nginx. $sudo service nginx start Starting nginx: nginx: [emerg] bind() to 0.0.0.0:80 ...
2
votes
3answers
67 views

(In)significance of [… ] and tty root processes

A colleague of mine assigned me to perform a root-cause analysis of an enterprise security server sometime ago. We knew the problem resided in one of the processes run by root but did not know which ...
0
votes
1answer
43 views

Issues executing program

Ultimately I'm trying to get a program to run at start up and work correctly. I have been successful in getting it to show up in running processes after a reboot, but it doesn't seem like it is ...
4
votes
1answer
592 views

Alternative to iotop for non-root user without sudo privileges

I'm looking for an alternative to iotop. Here's my situation: I want to find out if a program is accessing the hard drive a lot while running. iotop requires root/sudo privileges. My account is on ...
3
votes
1answer
259 views

Limit maximum number of concurrent scp processes running on a host

I am facing a problem where I have a fleet of servers which contain a lot of data. Each of the host runs many instances of a specific process p1, which makes several scp connections to other hosts in ...
2
votes
1answer
647 views

Where is PCB on linux

A PCB is a process control block , this is its definition on Wikipedia Process Control Block (PCB, also called Task Controlling Block,[1] Task Struct, or Switchframe) is a data structure in ...
4
votes
3answers
6k views

Fork bomb on a Mac?

I just learned about a fork bomb, an interesting type of a denial of service attack. Wikipedia (and a few other places) suggest using :(){ :|:& };: on UNIX machines to fork the process an infine ...
2
votes
3answers
1k views

CPU and Memory usage monitoring for a single process

I need to monitor the CPU and Memory usage for a single process in an AIX server. The program runs 3 times a day. I need to find the way to capture statistics within some time intervals, lets say ...
1
vote
2answers
599 views

How to monitor use of Huge Pages per process

I'm trying to determine which process is using a large number of Huge Pages, but I can't find a simple Linux command (like top) to view the Huge Page usage. The best I could find was $ cat ...
1
vote
1answer
181 views

How to find max parallel execution limit?

is there any limit for parallel execution? if yes, how to find out the maximum limit? I am creating a script which create a string of scripts concatenated by '&' and uses eval to execute them all ...
31
votes
2answers
10k views

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 | ...
1
vote
0answers
13 views

How to interpret numerous processes with exact same RAM usage [duplicate]

I have a VM that processes files, parses the information and saves it to a database. I've been monitoring the resource usage and noticed /usr/sbin/console-kit-daemon --no-daemon.. Below you see a ...
1
vote
2answers
117 views

How can a process appear to have different name in ps output?

recently I had to clean up a hacked server. The malicious process would appear as "who" or "ifconfig eth0" or something like that in "ps aux" output, even tough the executable was just a jumble of ...
0
votes
1answer
172 views

Process with randomized name

We have a centos server with customers running vps containers on it. When we run ps auxwww we see a randomly named process running (consuming a lot of bandwidth). Every time we check it is named ...
2
votes
3answers
169 views

how to run the dialog command with proccess

Please look on my code – ( bash script ) I want to display both dialogs on the screen on the same time, one dialog display the: tail –f from - /var/log/proccess1.log , and the second dialog ...
15
votes
3answers
2k views

How to know where a program is stuck in linux?

I am running the following command on my ubuntu server root@slot13:~# lxc-stop --name pavan --logfile=test1.txt --logpriority=trace It seems to hang indefinitely. Whenever this happened on AIX, I ...
1
vote
1answer
48 views

Remove Gnome Components detect by Packagename

I have tried out the dpkg, aptitude and apt commands. On the gnome desktop I decided to remove one component. sudo apt-get remove gnome-games or something else, all works fine. But if I don’t ...
0
votes
1answer
110 views

How does kill cascade in Linux? [duplicate]

Let us say I have process A which spawns process B, which spawns process C. Under what circumstances will killing A kill the whole chain (or tree I guess) and when will it not? I sometimes find it ...
1
vote
0answers
21 views

Spawning processes on a job stack

I have a hobbyist server on which I want users to upload a file, and then receive the overcome of some processing (server-side) over the given file. I am doing the processing synchronously so that for ...
0
votes
2answers
256 views

The program pstree and htop showing threads with unique PIDS. How is this possible?

I ran the program pstree -p 31872 which printed the following output: ruby(31872)─┬─{ruby}(31906) └─{ruby}(32372) The man page for pstree says: Child threads of a process ...
1
vote
1answer
298 views

How to use pgrep inside bash script correctly?

I'm running a GUI program called zeal(compiled from src) and add a script(zeal.sh) for the executable: #!/bin/bash if pgrep zeal &>/dev/null; then printf "already on\n" else ...
35
votes
6answers
74k views

How to find which processes are taking all the memory?

I'm looking for somthing like top is to CPU usage. Is there a command line argument for top that does this? Currently, my memory is so full that even 'man top' fails with out of memory :)
3
votes
3answers
106 views

How to view a specific process in top

Are there any relatively strightforward options with top to track a specific process? Ideally by identifying the process by a human readable value? e.g. chrome or java. In other words, I want to view ...