Disable unnecessary startup services and applications

Question

What is the best practices to disable unnecessary startup services and applications? This post is very useful when i came to decide what to disable Which startup applications can I safely disable? , but i cannot find how to start! also i cannot find anything related to services.

Answer 1

Go to the dock and search for Startup Applications. The GUI is very simple and you can remove programs from the list to stop them from automatically starting. Only remove programs that you know are not essential.

Answer 2

According to UpstartCookBook:

With Upstart 0.6.7, to stop Upstart automatically starting a job, 
you can either:

    - Rename the job configuration file such that it does not end with 
      ".conf".
    - Edit the job configuration file and comment out the "start on" stanza 
      using a leading '#'.

To re-enable the job, just undo the change.

Another better approach is:

With Upstart 1.3, you can make use of an "override file" and the manual 
stanza to achieve the same result in a simpler manner:

# echo "manual" >> /etc/init/myjob.override

Note that you could achieve the same effect by doing this:

# echo "manual" >> /etc/init/myjob.conf

However, using the override facility means you can leave the original job 
configuration file untouched.

To revert to the original behaviour, either delete or rename the override 
file (or remove the manual stanza from your ".conf" file).

manual stanza tell Upstart to ignore the start on/stop on stanzas.

In order to disable SystemV init service:

To enable/disable a service in a particular runlevel, you only need to
create/remove a symbolic link in a particular directory or set of 
directories.

This means that you should remove symbolic link in /etc/rc**runlevel**.d/NN**name** whose target is script /etc/init.d/name

Another better approach is update-rc.d command that can disable service:

   update-rc.d name disable

You can stop service and start service manually until /etc/init.d/name exists.

To disable service permanently, remove /etc/init.d/name.

Be careful what you do, disable service or job can result an unusable system.

Finally, this is a useful link on how to disable Gnome Session Startup applications and here another on How do I make a program auto-start every time I log in? where you can learn where information are stored and which GUI are available, so I guess you should find out how to disable session application on your system.