Bash tricks » History » Revision 5
Revision 4 (Alexis Jeandet, 30/03/2014 03:47 PM) → Revision 5/14 (Alexis Jeandet, 30/03/2014 03:48 PM)
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h1. Bash tricks
h2. Get disk usage
<pre><code class="bash">
df -h
</code></pre>
Will give you something like this:
<pre>
Sys. de fichiers Taille Utilisé Dispo Uti% Monté sur
/dev/sde1 110G 8,1G 97G 8% /
devtmpfs 126G 0 126G 0% /dev
tmpfs 126G 0 126G 0% /dev/shm
tmpfs 126G 920K 126G 1% /run
tmpfs 126G 0 126G 0% /sys/fs/cgroup
tmpfs 126G 4,0K 126G 1% /tmp
/dev/mapper/ddf1_DATA2 15T 7,7G 14T 1% /home
</pre>
h2. Get CPU and RAM usage
<pre><code class="bash">
htop
</code></pre>
Will give you something like this:
p=. !{width: 80%}htop.png(htop screenshot example)!
To get more information about htop see "here":http://htop.sourceforge.net/index.php?page=main
h2. Start a Job without a queue
All process started from ssh are terminated when you close the ssh connection, even if you fork them
(./app &). They are closed because when a process is closed the system send the SIGTERM signal
to all its children, it’s done to avoid zombies process on a machine. To keep your task alive when
you disconnect from ssh, you should use screen ("tutorial":http://www.rackaid.com/blog/linux-screen-tutorial-and-how-to/), it will block the SIGTERM signal. To
start your application with screen:
<pre><code class="bash">
screen # to start screen
./your_app #to start your application or any other command
#type ’ Ctrl-A’ Ctrl −A’ d to leave screen with your application running in background
</code></pre>
To reconnect to your previous session:
<pre><code class="bash">
screen -ls −ls # to list running sessions
screen -r 33287.pts-36.bender −r 33287.pts−36.bender # to reconnect to 33287.pts-36.bender 33287.pts−36.bender session
exit # to close your screen session
</code></pre>