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

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493 views

How to kill a process started as daemon?

I start a process using foo &. It outputs something like: [1] 16915 This is the process id, I guess. How can I store this number into a variable named MY_PROCESS_ID (for example)? Then I ...
0
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1answer
54 views

Script: Running a second process when the firts ended

I am trying to make a script that consist in a two parts. the first one is to run a initial state and the second one is to equilibrating the system. The problem is that the second is dependent of the ...
2
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1answer
93 views

Application lags if started from init.d?

I have a program (pre-compiled binary) that, when started manually on linux, runs fine. It has a CLI that I use to enter commands. This program is a software router, I can connect to it's CLI to ...
2
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2answers
690 views

Determine what java applications are running within the java process name

I am writing a Built System for Sublime Text 3 for JavaScript unit testing. I am using js-test-driver as my testing framework. Sublime Text can only execute one command, so I am using a bash script to ...
3
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2answers
387 views

Process in user mode switch to kernel mode. Then the process will have root privileges?

According to http://www.linfo.org/kernel_mode.html in paragraph 7: When a user process runs a portion of the kernel code via a system call, the process temporarily becomes a kernel process and is ...
3
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2answers
98 views

How to find out the reason a command/code was executed on Linux?

I have a complex embedded Linux software running on a gentoo derivative, on which a certain piece of code gets executed regularly every ~84 minutes. Sweeping through the main code to find places where ...
3
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1answer
52 views

Result from kernel returned to what process?

When a process requires actions that require kernel mode, it uses a system call. So, how are the results returned to the process?
3
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2answers
126 views

What does it mean exactly when a processes “Time” has stopped in top?

I'll be looking into why we're getting critical swap alerts, and I'll find something like: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ SWAP COMMAND 14683 user1 30 10 16.0g 772m ...
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1answer
368 views

How to get more information about Java processes from atop?

I have several java apps running on a machine and atop only tells me CMD java is there a way to get more information about that process, as I have +20 java in the list and I don´t know which one is ...
-1
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1answer
112 views

Which is the most precise command to get processes and system information? [closed]

I'm trying to evaluate performances of some active processes of mine on linux. Searching the internet I found that ps and top are the only command available for that. More precisely here, it says ...
0
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2answers
67 views

Check that fail2ban is running?

I just installed and configured fail2ban. I want to make sure it is working. I don't want to block myself from the server so I can't just login (poorly) a bunch of times. How do I see that fail2ban is ...
3
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3answers
803 views

Killing an instance of a process

This is an output from pstree In the picture you can see the marked boxes in which the processes are multiplied by a number? What is this number? I had a doubt that it is the number of instances ...
2
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1answer
722 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 ...
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3answers
176 views

How do I start a server via ssh and have it run after I log out?

I ssh into a virtual server and start up a web server. Everything runs as expected. But when I close my terminal on my laptop, the process dies on the virtual server. How do I fix this?
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2answers
82 views

How to limit the number of process that a user can create?

I think I have a program that creates countless forks of itself (not intentionally, I hope). I like to test this but I can't kill the machine, so how could I limit the number of process to execute ...
1
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2answers
295 views

Running a bash script as root prevents asynchronous execution?

The script below get's executed differently if run as a root user. #!/bin/sh gnome-terminal -x sleep 10 echo 'Why must I wait for sleep to finish?' If its run as a regular user, message is ...
1
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1answer
344 views

How to find out why a Java process died without a trace in Linux

A java process running in our SUSE Linux machine died without leaving a trace as to why it died. If it was killed with kill , it would have been logged and we would have known because the process ...
2
votes
1answer
2k views

What is the difference in CPU utilization between 'ps aux' and 'ps -ef'?

I use Ubuntu 12.04.1 Linux. I see a difference between %CPU and C output format of ps command for a process. It is not clearly noted in the ps man page. Man pages says: CODE HEADER ...
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0answers
104 views

Why is the service unavailable the second time?

How can this happen? /volume1/homes/me $ tdtool --list /volume1/homes/me $ tdtool -e 44 Learning device: 44 - Could not connect to the Telldus Service /volume1/homes/me $ tdtool --list Error fetching ...
7
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3answers
501 views

Harddrive I/O per Pid

is there any way to see the disk I/O per pid/process ? Monitorix shows me the following and correct me if I´m wrong, but it looks like that the harddrive is slowing down the whole system: UPDATE #1 ...
1
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2answers
134 views

Script always runs two instances

I was just curious, what may be the reason why script run two instances when executed. Whenever I run my script foo.sh, and when I check using: $ ps -ef | grep foo.sh It always returns two ...
0
votes
1answer
67 views

Can't terminate PHP daemon process

I've started a PHP daemon process via SSH with php ./my-script.php --daemon Now I want to quit this process, but I can't. It's still active in the foreground of my shell and I've hit CTRL + C ...
4
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4answers
8k views

Check for Process if Same is Running

Is there a script or a way in linux that when I try to execute a shell script/process, if the same is running, it will prompt that same is running and will exit otherwise it will continue.
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5answers
229 views

Replace instance of process in place?

I suspect this is not doable just because of the security implications, but here's what I'd like to do. Basically we run a bash shell-script on our CentOS server that calls Program-A (in our case ...
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2answers
3k views

In bash script, how to capture stdout line by line

In a bash script, I would like to capture the standard output of a long command line by line, so that they can be analysed and reported while initial command is still running. This is the complicated ...
4
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2answers
909 views

Why pidof and pgrep are behaving differently?

I have a init script in /etc/init.d/myservice for initialize a service like this: ... start() { ... daemon /usr/sbin/myservice ... } stop() { ... pgrep myservice pidof myservice ps -ef ...
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1answer
82 views

Can a script be running even after it's been killed?

I know it sounds so stupid and I know it IS stupid but I ran a unix script to send me and my friend emails every few seconds to test mailx. Stupid thing is I used $ while true; do blah blah blah... ...
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0answers
24 views

What is the [rc0] kernel process?

I have several servers. A few of them are running ubuntu 12.04 LTS. I'm looking into an intermittent hanging issue, and noticed an [rc0] kernel process From ps -ef: ... root 1025 2 0 ...
13
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1answer
11k views

There are stopped jobs (on bash exit)

I get the message There are stopped jobs. when i try to exit a bash shell sometimes. Here is a reproducible scenario in python 2.x: ctrl+c is handled by the interpreter as an exception. ctrl+z ...
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1answer
96 views

Why my cpu spend so much time on system? [closed]

top - 08:58:42 up 20 days, 8:23, 1 user, load average: 67.17, 58.94, 62.75 Tasks: 630 total, 40 running, 524 sleeping, 0 stopped, 66 zombie Cpu(s): 57.3%us, 41.6%sy, 0.0%ni, 0.0%id, 0.0%wa, ...
0
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2answers
76 views

Why does kill not have a parameter for file and not for port number?

If I want to stop a program given its tcp port number or its file or named executable, can I run something like kill -tcpPortNumber $1 where the parameter $1 is a tcp port number or kill -filename $1 ...
2
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1answer
662 views

Find the PID's of all threads of a process without ps or pidof

So the system I'm working on (BusyBox) has a ps that takes no command line arguments and pidof returns nothing even though it exists within /sbin and points to killall5. Another issue I had is that ...
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1answer
48 views

Is there a way to check which process terminates first during reboot

Assuming I have 2 processes running. Is there any way for me to check which process terminates first during reboot/shutdown? From this link, it tells about appending boot to a file. Yet, I still don't ...
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1answer
229 views

Track down process that has notty

I have a Linux server (Red Hat 2.6 kernel) which had a spike in load due to an Rsync process which seems to have forked many times, but the process was run by rsyncuser@notty I didnt see any cron job ...
2
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2answers
711 views

How can a normal user trigger a root cron task to execute immediately, without delay?

I have a root cron task that runs every day. But I want to allow normal users to request that it run immediately, if they so wish. It is a harmless process and it can run as often as needed and these ...
1
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1answer
154 views

spawning multiple Background processes

I have a file which has 2,000,000 lines in it. I am running some commands for each line. I was trying to achieve some parallelism using GNU-parallel and swift as discussed here. However, I got an ...
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1answer
229 views

Gnu Parallel: more than one per CPU? [closed]

If I only have two cores, does parallel only run two processes at a time? I guess I'm still confused about processes, threads, and cores....
0
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1answer
91 views

How can I rejoin a process running

I am very new to using Linux. I have a 'machine' on Amazon and I was trying to learn how to use Python on this machine. I started running Python—had to step away for a few minutes and the connection ...
0
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1answer
148 views

Full path name of bash? and base process of Linux?

I am new to Linux and I recently had a test at school which had the following questions: What is the full path name of bash? What is the base process of Linux? I couldn't answer these. Does anyone ...
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3answers
2k views

A command which returns either a process ID, if running, or some other output if not?

I'm looking for a command that will give me the PID, and it's not running it should give me some output other than blank. In my program, sometimes the library I'm using gives blank output even if ...
2
votes
1answer
179 views

How to move process from one namespace to other?

This question is similar to my question about how to list namespaces. So in addtition, I'd like to know some information about moving processes from one namespace to other? E.g. I have processes of ...
1
vote
1answer
61 views

How do I identify the user that is attempting to create a file?

I have a PHP script that is attempting to create a file, but it can not because of permissions. I would like to identify which user the system sees as the one requesting to create the file. I would ...
8
votes
1answer
681 views

how to find out namespace of a particular process?

I already asked a question about how to list all namespaces in Linux, but there wasn't any correct and exact answers, so I want to find out a method which can help me to find out the namespace of PID ...
2
votes
1answer
147 views

How to renice a group of processes?

lb build can build live system image, and it invokes many processes while building the image. If I start it as below: # nice -n 19 ionice -n 7 -c 3 lb build all the children processes get the same ...
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1answer
77 views

tftpd runs as root, despite explicit option “--user tftp”

I start my tftp server with the option --user tftp so that it runs as user tftp instead of root. However, ps shows that the process still runs as root ps aux| grep tftp root 2542 0.0 0.0 ...
70
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2answers
6k views

How does Linux “kill” a process?

It often baffles me that, although I have been working professionally with computers for several decades and Linux for a decade, I actually treat most of the OS' functionality as a black box, not ...
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2answers
1k views

How do I run two ongoing processes at once in linux/bash?

I would like to know how I can run two ongoing processes at the same time in Linux/bash. basically, I have a Node web server, and a MJPG-Streamer server. I want to run both these processes at once, ...
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3answers
6k views

How to get the Job ID? [duplicate]

As we know, the shell enables the user to run background processes using & at the command line's end. Each background process is identified by a job ID and, of course, by it's PID. When I'm ...
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2answers
290 views

Why do forked processes sometimes appear with brackets [] around their name in ps? [duplicate]

On a Linux system a C process is started on boot, which creates a fork of itself. It is not a kernal process or something. In most cases a ps -ef show both processes as expecxted, but sometimes it ...
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2answers
68 views

Increase nice value for many processes

Say I have launched a couple of non-timecritical applications such as a text editor a web browser etc and one more time critical (audio)application. Is there a utility that simulates the opposite of ...