A process is an instance of a computer program that is being executed.
3
votes
1answer
179 views
Cannot kill a java process
I have a java process that cannot be killed. I have tried every method I know, or that I have found on the internet to no avail. I have tried:
killall java
kill -9 <pid>
kill -11 <pid>
...
3
votes
1answer
1k 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.
3
votes
2answers
281 views
How can you determine which process scheduler is being used?
I.e. is it the O(1) scheduler, the CFS scheduler, or an older one?
3
votes
1answer
83 views
Get process list with logical intersection of selectors?
The Linux ps command allows multiple selectors, such as user and command name, but always returns the logical OR of those selectors (more than I want). Does anyone know of a method or tool already ...
3
votes
1answer
94 views
how to disallow user to change process group
Is it possible to restrict a process from changing it's process group? For example, user nobody seems to be able to call setpgid(0, 0) which sets process group of current process to pid of that ...
3
votes
1answer
546 views
Getting disk i/o statistics for single process in Linux
I need to monitor the I/O statistics of a process that writes to disk. The purpose is to avoid write rates too high for long periods.
I know there's iostat tool to accomplish this task on a ...
3
votes
3answers
199 views
Kill process when it stops to produce further output
Is there a shell tool which can probe if a subprocess is still producing output, and otherwise kill it after a specified timeout?
I'm using offlineimap for Gmail backup, but that's very very very ...
3
votes
1answer
640 views
A tee >( process ) is truncating its stdout when writing a file
When I use tee to pipe stdout directly to a "specific block of code" (which then writes the modified data to a file), I always get the full complement of exptected output lines in the file.
...
3
votes
1answer
376 views
Difference between process group and job?
What's the difference between a process group and a job? If I type pr * | lpr then is it both a process group as well a job?
What exactly is the difference between a process group ID and a job ID?
...
3
votes
1answer
105 views
What is “automatic stack expansion”?
getrlimit(2) has the following definition
in the man pages:
RLIMIT_AS
The maximum size of the process's virtual memory (address space) in bytes. This limit affects calls to brk(2), mmap(2) and ...
3
votes
1answer
367 views
When do jiffies increment? How a process runs in a jiffy?
I know that jiffies length is selected at kernel compile time and it is defaulted to 250 (4ms). Source: man 7 time - The Software Clock, HZ, and Jiffies
I wonder what happens inside a jiffy. What are ...
3
votes
1answer
520 views
Limit process resource consumption in CentOS 5 (2.6.18 kernel)
I would like to limit the resource (CPU, Memory, and network bandwidth) consumption of processes on the same server. And it will be good if I can migrate processes from one server to another.
I ...
3
votes
2answers
473 views
Process descendants
I'm trying to build a process container. The container will trigger other programs. For example - a bash script that launches running background tasks with '&' usage.
The important feature I'm ...
3
votes
2answers
660 views
How to trace a process to original user?
Say, on a Solaris server, user1 logs in, switches to someother user, say sruser, using su - and then starts a process of id X. And then another user user2 logs in, switches to sruser the same way and ...
3
votes
0answers
79 views
Elegantly get list of descendant processes
I would like to get a list of all the processes that descend (e.g. children, grand-children, etc) from $pid. This is the simplest way I've come up with:
pstree -p $pid | tr "\n" " " |sed "s/[^0-9]/ ...
3
votes
0answers
99 views
Can I get WCHAN from ps on Mac OS X 10.7.4?
From the manual it seems that ps -AO wchan should tell me what everything is sleeping on, but everything comes up as -. (And nwchan as 0). Did they do away with the old sleep()/tsleep() interface in ...
3
votes
0answers
265 views
Suggestions needed to debug why ps -ef gets stuck
A few of my processes consume 100% cpu. I'm trying to figure out which scripts are causing it
I tried running strace ps -ef:
open("/proc/PID/status", O_RDONLY) = 6
read(6, "Name:\textract\nState:\tR ...
3
votes
1answer
240 views
What is the need of the struct thread_info in locating struct task_struct?
While reading through the Linux Device Drivers, I could understand that the Process Descriptor (of type struct task_struct) has all the info regarding a particular task. The process descriptors are ...
2
votes
5answers
863 views
Graceful way to kill process
After my bash script is done with the selenium server, the script kills it like this:
kill `ps -ef | grep selenium | awk '{ print $2 }'`
While this works and it does kill the selenium script, it ...
2
votes
3answers
251 views
Why does a default Linux installation run more processes than a default OpenBSD installation?
If I ps -aux on Ubuntu (or any GNU/Linux distribution) without GUI I see ~100 processes running. If I ps -aux on OpenBSD without GUI, then I get ~10 processes.
What is the explanation/reason for ...
2
votes
2answers
90 views
What does d signify in processes like syslogd and httpd?
Why there is a "d" after the name of processes like syslogd and httpd ? What is its significance ?
2
votes
2answers
69 views
End process from another SSH window
I forgot to use screen and I have a task that has been running for quite some time, and I do not want to lose the saved data. Basically Ctrlc will end the task and save the data if I am on the same ...
2
votes
4answers
273 views
How do I know what service is running on a particular port in linux?
I am trying to run weblogic server on my linux machine and I am getting the following error :
ERROR: transport error 202: bind failed: Address already in use
ERROR: JDWP Transport dt_socket failed to ...
2
votes
2answers
90 views
$BASHPID And $$ differ in some cases
I'm reading "BASH pocket guide of Oreilly".
It said:
The process ID of the current Bash process.
In some cases, this can differ from $$.
Above explanation , explained $BASHPID variable.
...
2
votes
1answer
3k views
What does this process STAT indicates?
If you check the STAT column in above image you will see Ss S S< SN and R+
What does this indicates ? Process states.
If yes,Then what is the significance of 'Ss S< SN and R+'?
2
votes
2answers
982 views
killing a process on a remote machine when the machine is stuck
I started a very resources-consuming process on a remote server via ssh. It is an optimization problem run in MATLAB. It takes full memory and CPU. In fact, I am not even able to ssh to the machine, ...
2
votes
4answers
541 views
How to run java process to be seen not as 'java…' in processes list?
Is it possible to run a Java process in Linux in a way that it could be seen in ps as some sort of alias? It would be easier to restart it when it is down.
2
votes
2answers
217 views
Is there any impact of reaping zombie processes?
I will execute following command for reaping zombie
/usr/bin/preap $(ps -ef | grep defunct | grep -v grep | awk '{ print $2 }' | xargs)
Is there any service impact of this approach ?
2
votes
2answers
744 views
Do sleeping processes get the same CPU time?
Some processes spend most of their "lives" in a sleep status. Daemons, servers and general listener come to mind. I was wondering if they get the same CPU time in that state? On something like my ...
2
votes
4answers
572 views
How to get a process uptime under different OS?
Under Linux I can get a process's uptime in seconds with:
echo $(($(cut -d "." -f1 /proc/uptime) - $(($(cut -d " " -f22 /proc/$PID/stat)/100))))
But how can I get it under different OS? ex.: ...
2
votes
3answers
428 views
How can I test if a program is running from within a script
Let's assume that another user started a bunzip process, and I have a script that I'd like to start running after that bunzip finishes. What's the best way to check from inside my script that the ...
2
votes
1answer
803 views
A more readable ps
Are there any tools that improve the readability of ps in the same spirit as ack for grep?
This would be especially on OS X where ps does not even have options such as --sort user.
So far the nicest ...
2
votes
4answers
4k views
What is a command line alternative to top for finding current CPU utilization that isn't dependent on screen width?
If I run top -p <myPID> -n 1 with a terminal that isn't wide enough, the CPU utilization % is omitted from the output. When trying to find a process' cpu utilization via bash scripting, this is ...
2
votes
2answers
317 views
I need help with a cronjob to watch for runaway processes and kill them
I have an interesting situation, I have a runaway ruby process - I know exactly how I trigger it.
Point is, it got me thinking about runaway processes (CPU usage or memory usage).
How would one ...
2
votes
1answer
128 views
How to find Heap memory of a running process? [duplicate]
I would Like to know how to find the heap captured of a process which is running in the background?
Is there any command by which you can find the process heap memory and here the process is still ...
2
votes
3answers
113 views
How do I start a process with a nice value of -20 and not give it root privilege?
I would like to start a process with a nice value of -20. This requires me to use a command like - sudo nice -n -20 matlab. However, this starts matlab as root too. Is there a way to have matlab as ...
2
votes
1answer
207 views
What does kill 0 do actually?
In the man page, it says:
kill [ -s signal | -p ] [ -a ] [ -- ] pid ...
pid... Specify the list of processes that kill should signal. Each pid can be one of five things:
0 All ...
2
votes
3answers
141 views
Why does Firefox refuse to die despite killing it with pkill -9?
I am issuing the following command to kill Firefox on my Red Hat Linux box:
[subhrcho@slc04lyo ~]$ pkill -9 -f firefox
[subhrcho@slc04lyo ~]$
However, when I try to invoke Firefox through ...
2
votes
2answers
517 views
Find the PID of top CPU/MEM usage, save to a shell variable
Is there any way to get the PID of the top CPU/MEM usage, I need to use that in a script, top command doesn't seem to work for it.
2
votes
2answers
821 views
Killing a running process in an Ubuntu machine remotely from a windows machine which is in LAN
Is it possible to kill a process running in an Ubuntu machine from a Windows (XP) machine remotely connected via LAN?
I can kill the process in a windows machine from a remote windows machine (in ...
2
votes
2answers
99 views
Where is the virtual memory stored on hard drive?
If a process wants to access a memory address that is not in physical memory, the OS outsources a page frame from physical memory to the hard drive for later use. Where on the hard drive is this data ...
2
votes
2answers
65 views
what happens when a window manager is put to background
I am trying to understand the situation why .xsession file expects the last process to be in foreground otherwise it is supposed to stop X11 session.
I have a small stand-alone script. when I run ...
2
votes
4answers
432 views
How to view the output of a running process in another bash session?
I have left a script running on a remote machine from when I was locally working at it. I can connect over SSH to the machine as the same user and see the script running in ps.
$ ps aux | grep ...
2
votes
4answers
130 views
How to find out what is this process for?
I have this 'java' process running for 3 hours ( I guess ). I didn't see it before and I wonder how could I find out where it's coming from?
Here is a screenshot:
EDIT: ok I figured it out, it's ...
2
votes
2answers
89 views
How to constrain the resources an application can use on a linux web server
This is the situation:
I have a PHP/MySQL web application that does some PDF processing and thumbnail creation. This is done by using some 3rd party command line software on the server. Both kinds of ...
2
votes
2answers
180 views
Quick and dirty way to run a process more than once
I am looking for very simple bash script that would allow me to launch a process a few times. What's essential to me is that after the processes terminate, everything will clean up automatically.
...
2
votes
3answers
385 views
What is meant with terminating a process normally?
In an examination it is stated:
Give 2 different ways that a process can terminate normally. Describe
the differences.
What is meant with terminate normally?
2
votes
1answer
430 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 ...
2
votes
2answers
490 views
Removing zombie process from the process table
Can somebody please explain when parent process receives the exit status of a dead child process via wait, who actually reallocates the memory of the child process and removes it from the process ...
2
votes
4answers
62 views
Open program as root, close root session but still program is running
When I run my backup script, first I switch to root, mount a truecrypt partition and then run the script.
I've noticed that after run truecrypt as root, I can exit the root session and truecrypt ...
