Questions tagged [process]
A process is an instance of a computer program that is being executed.
2,588
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Send signal to process in tmux pane
Suppose that app X is running in the foreground in tmux pane. I'd like to send a given signal, e.g. SIGUSR1, to app X. Can I configure a tmux keybinding to send a signal to the currently-selected pane'...
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What is the webkitwebprocess in linux?
So the other day I was looking for a ultra light weight browser. Midori was the first option as per internet. But this was the RAM usage of it.
RAM USAGE
though midori took only around 100MB, the ...
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Is it possible to redirect a paused process into a new pipe?
Suppose I have a process that takes some time and outputs some JSON.
$: ./foo.py file
{ ... }
And I have piped this output into jq:
$: ./foo.py file | jq .
And I say: oh no -- the output is long, ...
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How to calculate CPU utilization for an application in a multicore system
On 8-core server, 0-3 are configured as isolcpus and remaining cores (4-7) are available for system and user processes to run. My application has multiple processes which will run on any one of the ...
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how to avoid delete files that comes from gdm-session & cause of increasing used /var
from lsof we can see the following output
lsof /var | grep delete
rsyslogd 9664 root 4w REG 253,2 25589554694 67267903 /var/log/messages-20210513 (deleted)
rsyslogd 9664 root ...
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run daemon process and run next process
I have a shell script and it has 3 program:
#!/bin/bash
x
y
z
each of above programs is binary and have to run in order.
program y is a daemon. When bash run x, it's okey and when y is running, z can'...
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How to find the number of jobs (created by gnu parallel) running in each CPU core at any given time?
I'm using gnu parallel that reads a text file containing curl commands.
If I do ps -ef | grep -cw [c]url it shows total number of curl process at a moment.
But I want to know number of gnu parallel ...
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killing multiple processes listed in a file
I'm trying to build a script where it will verify, from a file, if the listed processes are running and if they are, they should be killed.
this file contains similar list to:
process01:0
process02:0
...
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360
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Are these threads in htop using any resources?
My node application spawns ffmpeg processes. In htop, there are a bunch of ffmpeg processes I would have expected to have ended but they are still shown in htop. The threads in green are the process ...
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Practically unfork process
I have an executable binary (no source) that clone()s.
It doesn't print anything and I think the child is trying to, which I'd like it to do.
It always returns successfully even when the child ...
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Why or how does killing the parent process clean the zombie child processes in linux?
Consider this example -
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
int main()
{
pid_t pid = fork();
if (pid > 0)
{
printf("Child pid is %d\n", (...
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Debug an instantly failing/never appearing child process
I have an executable binary (it's a device driver).
It runs and instantly exits with a successful 0 return code.
On one computer it creates the all important child process I can see with pgrep, but ...
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Xen: is possible to see processes of the domU on dom0?
I have installed on a Debian dom0 a paravirtualized domU(Opensuse)
When I use lxc I can see the process with the "translated" uid
for example, on a Slackware lxc "host" I can see ...
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C language programs not workning on ubuntu
I wrote a simple code to find even and odd numbers in c.
#include <stdio.h>
int main() {
int num;
printf("Enter an integer: ");
scanf(" %d", &num);
(num % 2 =...
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2
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What are CGroup Slices Used For
Just been paying attention to systemctl status' branching structure. I realized I was making up stories to explain why it looked like that but had no clue of what it meant. I can't find much info on ...
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How to list all processes by non-root users?
I want to see a list of processes similar to what ps aux outputs but not show any root processes.
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How can I kill a specific process running inside a screen session, without killing that screen session?
I have run multiple ANN training processes under multiple screen sessions. When I enter a screen, I see a training process running.
Now, I want to kill a specific process inside the screen without ...
- 375
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1
answer
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Unexpected behavior when checking file size
I'm trying to write a 1 line bash script that will get all PIDs of processes that look like kernel processes, and check to see if they have contents in /proc/*/maps, which indicated kernel process ...
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Is signal handling a property of a process or not?
From reading the standard, I understand that:
signal handling is a property shared by all threads of a process;
signal mask is a per-thread property.
However, the standard list the following (In ...
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Kill process once it produces certain output
I'm running a program which executes (mostly) correctly, but then hangs. I'd like to run the program such that once it outputs a certain string, or stops producing output it gets killed.
The output ...
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How to block the internet access but allow local host connection in a process
I have a python program with 2 process running in docker:
my own server listening at 8080
an application listening at 8000
I am trying to block the internet access for the 2nd process. I was able to ...
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Subshell (subprocess/child process) with its own $BASHPID not listed by `ps`
I don't understand the following:
mkfifo p;
$ (>p ps -f | >>p echo $BASHPID) &
[1] 983527
$ cat p
983529
PID PPID C STIME TTY TIME CMD
981815 165343 0 19:57 pts/27 00:...
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Example of subshell without child-shell process
I just recently learned that "subshell" is not the same as "child shell process" (see for example What is the exact difference between a "subshell" and a "child ...
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Creating an orphan process
Using Ubuntu, can I create an orphan process by killing the parent process of a background process of sleep 1000 command? Is it possible?
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How to check if process with pid X is the one you expect
In our application, we start some background processes. The pid of these processes is saved to a file.
pids values are re-used when the maximum is reached or when the system is rebooted.
How can I ...
- 441
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How to keep a timing dependent C process from context switching
We have a process that is responsible for polling hardware at time-dependent intervals. We would like to dedicate a CPU core to this process. E.g. we want this process to remain runnable at all times.
...
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To persist a namespace, create a bind mount point on which /proc/PID?
From https://man7.org/linux/man-pages/man1/n.1.html :
By default, a new namespace remains in existence only as long as it
has at least one member process. A namespace can be made persistent—
that ...
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Filter processes by name and nice number
I'm trying to create a script to find the PID number with only the process name and nice number, but I'm not able to.
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process not killed even we used kill -9 and process actually was belong to container that already removed
here is a strange behavior that show how to kill a process , but actually process not killed
example ( from rhel 7.6 server )
ps -ef | grep kafka-exporter
root 15340 19528 0 17:25 pts/0 00:00:...
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SIGHUP strange behavior
Context:
I am running a process from bash without & and any redirection i.e like ./foo. The process is running while(1) i.e it is running forever. Also, the process is ignoring SIGHUP i.e not ...
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Bash: command substitution with background job
I'm trying to fire and forget a process within a function in bash.
I'd this function to return a status corresponding to the fact the process has indeed been fired and retrieve output of the function ...
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A process is running and I cannot find what is it and cannot kill that!
I've found a bash process in my Ubuntu server that is consuming all of my CPU
I've try to kill this process by kill -9 and after kill the process run automatically
How can find what is this process ...
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Debugging ssh connection that prints incorrect characters to terminal what appears randomly after ssh logins
With random occurence for ssh logins into remote terminal ('agetty') there is immediate output of unrelated characters into that ssh session terminal.
With periodical repetition these are "hh��...
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Documentation on the value of $$ in a background process
Is there a documentation on the value of $$ in a background process in bash?
man claims that $$ in a subshell is the PID of the main process.
According to the following documentation, a subshell is ...
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Bash $$ in backgrounded process [duplicate]
According to the man, $$:
Expands to the process ID of the shell. In a () subshell, it expands
to the process ID of the current shell, not the subshell.
I did some testing:
$ echo $$
20823
$ echo $$...
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Why do threads have their own PID?
I'm using htop and looking at a process (rg) which launched multiple threads to search for text in files, here's the tree view in htop:
PID Command
1019 |- rg 'search this'
1021 |- rg 'search ...
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How to redirect running process output from pipe to something else?
Is there any way to redirect stdout (1) from that "pipe" (I don't know exacly how I suppose interpret this, I will be glad if someone could explain how to treat this, or give me some read on ...
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Create a histogram in unix using simple bash commands [duplicate]
I have a huge file with almost 1M lines. I want to create a histogram based on the contents of the file. The values in the file would look something like this:
0.0488
-0.0342
0.0345
-0.0524
-0....
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510
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Why PID 1 send SIGTERM
I had this problem for a few days.
A process, in this case qbittorrent, will stop after a few minutes.
Looking at logs it seems that it just caught a SIGTERM.
Alright so I used strace -p {PID} -e '...
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Which process initiates outgoing connections?
Nearly every second an unkonwn process tries to establish a connection to one of my servers:
192.168.4.3.59582 > 192.168.3.42.49152: Flags [SEW], cksum 0x8bc5 (correct), seq 3191149618, win ...
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Skip loop iteration(s) interactively on keypress
I am looping over an array and for each iteration, run a long during process, like this:
!#/bin/bash
arr=({1..100})
for i in "${arr[@]}"; do
echo "$i"
sleep 10
done
Now I ...
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pid for child of child processes
i'm running a script that calls a child script that in turn calls other child scripts and processes.
some of the child processes use a lot of disk io and cpu, and overheats the cpu, causing a crash or ...
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538
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How do I know what process is running for a systemd-timers service?
I'm trying to determine whether a process is running successfully for a service that's scheduled as a systemd-timers service. I have a service scheduled called certbot.service, which I can see using ...
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Run foreground process until background process exited in shell
I'm running QEMU virtual machine in -daemonize mode and then spawn an arbitrary foreground (possibly interactive) process intended to interact with the QEMU instance. In general once foreground ...
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490
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Get CPU usage for past n seconds or minutes
Is there a magic command in Linux for listing the processes active in the last past n seconds by CPU usage?
To clarify: Process A is launched and it takes 5 seconds to complete, about 5 more seconds ...
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Does a process' kernel virtual memory contain process specific data?
I don't quite understand this picture from the CS:APP book.
It shows how the kernel virtual memory of a process has a region different from other processes.
Does this mean, that the kernel in the ...
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Why the value of PRI is different in ps and top?
nginx PID is 19910
The value is 19 in ps -eo pri
ps -eo pid,ppid,ni,pri,psr,pcpu,stat,cmd |head -n1;ps -eo pid,ppid,ni,pri,psr,pcpu,stat,cmd |grep nginx
PID PPID NI PRI PSR %CPU STAT CMD
19910 ...
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How does the page table of a process knows which page was swapped?
I'm refering to those links:
Page table content when the physical page we are looking for is in swap area
how does linux update page table after context switch
How does the kernel address swapped ...
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44
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Is it possible to make a device accessible exclusively by certain programs?
I have a device (a video card) that I need only two programs (expressed as paths, e.g. /usr/bin/myprogram) to access.
The device has a /dev file (e.g. /dev/mydev1), but I can also use other references ...
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Is there a way to monitor L1, L2 and L3 cache usage with command line?
I'm looking for a way to know, using command line, how much CPU mem cache is using a running process... is there a way to do that?
Thanks in advance
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