Commands tagged processes (18)

  • processes per user counter

    awk is evil! Show Sample Output


    22
    ps hax -o user | sort | uniq -c
    buzzy · 2010-04-29 10:43:03 13
  • FAST Search and Replace for Strings in all Files in Directory

    I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time. Show Sample Output


    10
    sh -c 'S=askapache R=htaccess; find . -mount -type f|xargs -P5 -iFF grep -l -m1 "$S" FF|xargs -P5 -iFF sed -i -e "s%${S}%${R}%g" FF'
    AskApache · 2009-10-02 05:03:10 7
  • processes per user counter

    enumerates the number of processes for each user. ps BSD format is used here , for standard Unix format use : ps -eLf |awk '{$1} {++P[$1]} END {for(a in P) if (a !="UID") print a,P[a]}' Show Sample Output


    6
    ps aux |awk '{$1} {++P[$1]} END {for(a in P) if (a !="USER") print a,P[a]}'
    benyounes · 2010-04-28 15:25:18 3
  • Sort processes by CPU Usage

    Short list about top 10 processes, sorted by CPU usage Show Sample Output


    3
    ps aux | sort -rk 3,3 | head -n 10
    x3mboy · 2018-10-29 20:00:36 571
  • Sort processes by CPU Usage


    3
    ps auxk -%cpu | head -n10
    rolanda · 2019-06-29 19:17:14 46
  • Schedule Nice Background Commands That Won't Die on Logout - Alternative to nohup and at

    Check out the usage of 'trap', you may not have seen this one much. This command provides a way to schedule commands at certain times by running them after sleep finishes sleeping. In the example 'sleep 2h' sleeps for 2 hours. What is cool about this command is that it uses the 'trap' builtin bash command to remove the SIGHUP trap that normally exits all processes started by the shell upon logout. The 'trap 1' command then restores the normal SIGHUP behaviour. It also uses the 'nice -n 19' command which causes the sleep process to be run with minimal CPU. Further, it runs all the commands within the 2nd parentheses in the background. This is sweet cuz you can fire off as many of these as you want. Very helpful for shell scripts.


    2
    ( trap '' 1; ( nice -n 19 sleep 2h && command rm -v -rf /garbage/ &>/dev/null && trap 1 ) & )
    AskApache · 2009-10-10 04:43:44 7
  • Viewing Top Processes according to cpu, mem, swap size, etc.

    I've wanted this for a long time, finally just sat down and came up with it. This shows you the sorted output of ps in a pretty format perfect for cron or startup scripts. You can sort by changing the k -vsz to k -pmem for example to sort by memory instead. If you want a function, here's one from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html aa_top_ps(){ local T N=${1:-10};T=${2:-vsz}; ps wwo pid,user,group,vsize:8,size:8,sz:6,rss:6,pmem:7,pcpu:7,time:7,wchan,sched=,stat,flags,comm,args k -${T} -A|sed -u "/^ *PID/d;${N}q"; } Show Sample Output


    2
    command ps wwo pid,user,group,vsize:8,size:8,sz:6,rss:6,pmem:7,pcpu:7,time:7,wchan,sched=,stat,flags,comm,args k -vsz -A|sed -u '/^ *PID/d;10q'
    AskApache · 2010-05-18 18:41:38 6
  • Shows users and 'virtual users' on your a unix-type system

    Shows a list of users that currently running processes are executing as. YMMV regarding ps and it's many variants. For example, you might need: ps -axgu | cut -f1 -d' ' | sort -u Show Sample Output


    2
    ps -eo user | sort -u
    dfaulkner · 2010-07-07 12:28:44 6
  • See how many more processes are allowed, awesome!

    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. OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 )) 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. find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' 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: cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' 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. cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' 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. Show Sample Output


    1
    echo $(( `ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l` ))
    AskApache · 2010-03-12 08:42:49 6
  • processes per user counter

    use Linux ;) Show Sample Output


    1
    pgrep -cu ioggstream
    ioggstream · 2010-05-21 10:53:57 4
  • View All Processess Cmdlines and Environments

    Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have. Here's a function I use: aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "<{}/cmdline&&echo&&tr -s "\000\033" "\nE"<{}/environ|sort&&cat {}/limits' ); } From my .bash_profile at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    1
    cd /proc&&ps a -opid=|xargs -I+ sh -c '[[ $PPID -ne + ]]&&echo -e "\n[+]"&&tr -s "\000" " "<+/cmdline&&echo&&tr -s "\000\033" "\nE"<+/environ|sort'
    AskApache · 2010-10-22 02:34:33 14
  • processes per user counter

    No need for sort Show Sample Output


    1
    ps hax -o user --sort user | uniq -c
    sharkhands · 2016-09-15 23:31:51 15
  • See how many more processes are allowed, awesome!


    0
    echo $(($(ulimit -u)-$(pgrep -u $USER|wc -l))
    h3xx · 2011-07-30 05:03:36 3
  • Threads and processes of a user

    This shows all process (-e) and threads (-L) in full format (-F) Show Sample Output


    0
    ps -eLF | grep ^user
    balsagoth · 2013-07-24 09:53:12 10
  • Threads and processes of a user

    Piping ps into grep is mostly useless: ps has its own filter options like -u and -C Show Sample Output


    0
    $ ps -LF -u user
    jld · 2013-08-06 21:50:48 12
  • List user processes with their memory usage and total usage.

    Add up the amount of memory your processes are using and display the total. Replace marcanuy with your desired username. Show Sample Output


    0
    ps -u marcanuy -o pid,rss,command | awk '{print $0}{sum+=$2} END {print "Total", sum/1024, "MB"}'
    marcanuy · 2013-11-20 01:21:59 7
  • Get all ProcID's for a given process

    If you have to stop a bunch of processes or just want to get a list of their ID's, us this replacing with your process. Then you can use a loop to kill -9 all of them. Show Sample Output


    0
    sudo <PROC_NAME> -aux |grep pals_ |tr -s " " |cut -d " " -f2
    dskzz · 2016-06-05 02:14:10 12
  • Shows users and 'virtual users' on your a unix-type system


    -3
    ps -axgu | cut -f1 -d' ' | sort -u
    dfaulkner · 2010-07-07 12:29:46 4

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Check These Out

Save your terminal commands in bash history in real time
Use this command if you want your terminal commands be saved in your history file in real time instead of waiting until the terminal is closed

print all network interfaces' names and IPv4 addresses
ifconfig can't properly display interface's name longer 9 symbols,also it can't show IPs added thru ip command, so 'ip' should be used instead. This alias properly shows long names, bond interfaces and all interface aliases. loopback interface is ignored, since its IP is obvious

Reset terminal that has been buggered by binary input or similar

Check for Firewall Blockage.
This is just one method of checking to see if an IP is blocked via IP tables or CSF. Simple and to the point. Replace xx.xx.xx.xx with the IP you wish to check.

run complex remote shell cmds over ssh, without escaping quotes
It executes commands as arguments to ssh, avoiding problematic shell expansions, without the need of writing the commands in question to a temporary file, just reading them from STDIN.

List all authors of a particular git project
This should work even if the output format changes.

list all file extensions in a directory
Just a little simplification.

Find status of all symlinks
The symlinks command can show status of all symbolic links, including which links are dangling, which symlinks point to files on other file systems, which symlinks use ../ more than necessary, which symlinks are messy (e.g. having too many slashes or dots), etc. Other useful things it can do include removing all dangling links (-d) and converting absolute links to relative links (-c). The path given must be an absolute path (which is why I used $(pwd) in the example command).

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

Randomize lines in a file
Works in sort (GNU coreutils) 7.4, don't know when it was implemented but sometime the last 6 years.

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: