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

learn more… | top users | synonyms (1)

1
vote
2answers
1k views

Discrepancy between reported used memory and sum of application memory usage

I'm running a desktop system that quite regularly suffers from lack of memory, this prompted me to investigate what causes the issue in the first place. Problem is, there's no single process that ...
3
votes
1answer
67 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
48 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
258 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
5k 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
145 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
69 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
56 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 ...
25
votes
2answers
7k 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
32 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
28 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
37 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
1k 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
25 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
58 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
1answer
85 views

How to check which process is using most memory

When I check free in one of Prod server it showing 70% of memory is being used: total used free shared buffers cached Mem: 164923172 141171860 23751312 ...
1
vote
0answers
18 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
92 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
29 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 ...
30
votes
6answers
56k 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
67 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 ...
26
votes
5answers
16k views

How to determine which process is creating a file?

Given file path, how can I determine which process creates it (and/or reads/writes to it)?
9
votes
4answers
3k views

Why is SIGINT not propagated to childs process when sent to it's parent process?

Given a shell process (e.g. sh) and it's child process (e.g. cat), how to simulate the behavior of CTRL+C using the shell's process ID? This is what I've tried: Running sh and then cat: ...
2
votes
2answers
241 views

set packet rate limit via iptables

I have a packet rate limit (max. 10 per seconds) which is set by my internet provider. This is a problem if I want to use the AceStream player, because if I exceed the limit I get disconnected. How ...
1
vote
0answers
39 views

monitor a process by matching the full cmdline

I'm looking for a software that can monitor a process (specified as a partial string/regexp match (e.g. grepping) in its full command-line) in terms of cpu and memory usage. If any of those processes ...
5
votes
3answers
1k views

How to poll existence of a background script correctly

I have a problem with the following kind of script: #!/bin/sh long_running_script.sh & while [ `pidof long_running_script.sh` ] do echo "." sleep 1 done The sript will ...
4
votes
2answers
1k 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 ...
2
votes
1answer
650 views

Using `pidof` with `sh -c`

I was wondering why this command line does not print pidof sh: $ sh -c "var=`pidof sh` ; echo \$var; ps -H" This one prints 123 as expected $ sh -c "var=123 ; echo \$var; ps -H" I am on Ubuntu ...
3
votes
2answers
313 views

When vfork is called is parent process really suspended?

As much as I know when vfork is called child process uses the same address space as that of the parent and any changes made by the child process in parents variables are reflected onto parents ...
9
votes
2answers
173 views

Print pids and names of processes as they are created

From the question here, the OP wants to repeatedly poll the pid of a process using pidof in a shell script. Of course this is inefficient as a new process must be started for the pidof program ...
7
votes
4answers
488 views

How to find source of spawning process?

I have a Java process running on a RedHat Linux instance. The problem is it keeps reappearing after I kill it. I am not sure where to look. I've already went to crontab, but no luck. I've looked at ...
1
vote
0answers
79 views

Are there any alternatives to pidof? (smaller footprint)

Well, I've just found out that with extensive usage of pidof in very short intervals, the seemingly tiny tool can be a great CPU hog. (Source: top) On my older machine, it can easily reach 30 percent ...
11
votes
3answers
13k views

Find out what processes are writing to hard drive

On my Lenovo T400 and Ubuntu, the light for hard drive writing keeps flashing. I was wondering if in Linux it is possible to find out what processes are doing I/O to the hard drive? Just like by top, ...
1
vote
1answer
31 views

What is the meaning of every column when executing psig command?

I try to use psig command to track signal dispositions of a process on Solaris: bash-3.2# psig 3109 3109: bash HUP caught termsig_sighandler 0 ...
7
votes
2answers
606 views

Simulate an unkillable process in D state

For catastrophe testing scenarios on out server environment we're looking for an easy way to make a process stuck in D (uninterruptible sleep) state. Any easy ways? An example C sample code would be ...
4
votes
3answers
130 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 ...
3
votes
1answer
40 views

How to find the file corresponding to a pipe opened by a process? [duplicate]

I created this script, which listens for characters received on a hardcoded pipe, and tries to eval those characters. I call my script loop_executor.sh This is all it contains: !/bin/bash while : do ...
1
vote
4answers
2k views

Why teamviewer starts again after being killed

My main desktop has Mint 14 and I approached it via SSH from another computer, because I didn't have a screen on the Mint one. Then I tried to start teamviewer just I order to launch its desktop ...
3
votes
0answers
63 views

Kill a whole process tree regardless different GIDs

I am having issues with process control using the signals available to the process abstraction. In the example below you can see there is a perl script which is the parent of the whole tree with a ...
24
votes
4answers
3k views

What's the difference between running a program as a daemon and forking it into background with '&'?

What are the practical differences from a sysadmin point of view when deploying services on a unix based system?
1
vote
1answer
46 views

Types of sleep modes for processes

I came across this while troubleshooting why our server is doing down everytime the oracle process is killed. I listed the oracle process running on the server using ps aux | grep oracle and here is ...
3
votes
1answer
74 views

Why does the 'user' and 'sys' time vary on multiple executions?

There is a nice question and answer explaining the relationships between 'real', 'user' and 'sys'. It explains the reasons why 'real' can vary, and defines the 'user' and 'sys' as times the process ...
6
votes
1answer
301 views

Is there a way to see if process listening on TCP port receives a message?

According to tcpdump, my server receives the following TCP packet: 12:52:29.603233 00:19:e2:9e:df:f0 00:16:3e:6a:25:3f, ethertype IPv4 (0x0800), length 74: 10.10.10.65.38869 192.168.215.82.22: ...
2
votes
1answer
99 views

How to change the kernel max PID number? [duplicate]

The default PID max number is 32768. To get this information type: cat /proc/sys/kernel/pid_max 32768 or sysctl kernel.pid_max kernel.pid_max = 32768 Now, I want to change this number... but I ...
2
votes
2answers
55 views

How can I make a for loop starting a lot of processes?

I want to test some bug, and to do that I need to have a situation where the PID is larger than 99999. I am thinking of a bash script, a for loop. Any ideas?
0
votes
1answer
72 views

Kill unresponsive process by name but preserve responsive processes

For some reason, I end up with a fair few Google Chrome Helper processes which stop responding, hogging CPU resources. Usually I just run killall Google\ Chrome\ Helper, however this kills all, ...
0
votes
2answers
58 views

How to trick an application to run different processes?

I am running PDFXCview.exe (for pdfxchange viewer portable version) under wine to open a pdf file, by PDFXCview.exe 1.pdf When I do the same for another file, the other file will be opened by the ...
0
votes
2answers
66 views

What determines if an executable can be run in different independent processes simultaneously?

I posted a question about how to run an executable (a PDF viewer) under wine independently in multiple processes (independent means no communication between them, it is not parallel computing). I ...
2
votes
0answers
57 views

Why do some processes pass on their cpu usage to another process when it ends?

I have wondered this for a while. For example, lets say process1 is a process that uses a lot of cpu power, like 90%. Its a video game. Then i have process2 which uses 10-12% cpu. Its a web browser. ...