Commands tagged kill

Use this if you can't type repeated killall commands fast enough to kill rapidly spawning processes.

If a process keeps spawning copies of itself too rapidly, it can do so faster than a single killall can catch them and kill them. Retyping the command at the prompt can be too slow too, even with command history retrieval.

Chaining a few killalls on single command line can start up the next killall more quickly. The first killall will get most of the processes, except for some that were starting up in the meanwhile, the second will get most of the rest, and the third mops up.

dcfldd is a forensic version of dd that shows a process indicator by default.

The 'dd' command doesn't provide a progress when writing data. So, sending the "USR1" signal to the process will spit out its progress as it writes data. This command is superior to others on the site, as it doesn't require you to previously know the PID of the dd command.

Another way of counting the line output of tail over 10s not requiring pv.

Cut to have the average per second rate :

tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2

You can also enclose it in a loop and send stderr to /dev/null :

while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

or "Execute a command with a timeout"

Run a command in background, sleep 10 seconds, kill it.

You can test it with:

find /& sleep10; kill $!

Useful command to get information about running java process and treads, to see log look into the default log for your java application

There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100.

This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript).

An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command.

I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this:

I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this.

If you were building a process-killer (very common for cheap hosting) this would also be handy.

Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

This is a more accurate way to watch the progress of a dd process. The $DDPID=$! is needed so that you don't get the PID of the sleep. The sleep 1 is needed because in my testing at least, if you run kill -USR1 against dd too quickly, it will kill it off instead of display the status. So you need to wait a second, probably so that it can configure itself to trap the USR1 signal.

Kills a process matching program. I suggest using

$ pgrep -fl program

to avoid over-killings

Nice the following: kills all bash process owned by guest

$ pkill -9 -f bash -u guest

Just find out the daemon with $ netstat -atulpe. Then type in his name and he gets the SIGTERM.

Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.

explanation:

grep -- displays process ids

-v -- negates the matching, displays all but what is specified in the other options

-u -- specifies the user to display, or in this case negate

The process loops through all PIDs that are found by pgrep, then orders a forced kill to the processes in numerical order, effectively killing the parent processes first including the shells in use which will force the users to logout.

Tested on Slackware Linux 12.2 and Slackware-current