Speeding up Application Startup Times with ureadahead
, 20 Aug, 2010
The faster a system, the merrier—that is the latest fashion fad in IT. Looking at the Ubuntu developers to-do list, one can find boot optimization a high priority. Instead of improving the actual boot process (which is difficult for end-users; though sysv-rc-conf does a great job disabling not needed startup applications), this article deals with a simple tool speeding up applications starts.
über-readahead is a tool which analyzes the boot process and checks which programs and libraries are loaded during and directly after the system startup. It marks these files and preloads them henceforth, which results in often used applications being started much faster. In my configuration that is the case for Firefox, Thunderbird, Pidgin and the terminal. If the boot sequence changes, ureadahead is triggered. If so, it dumps the cache database and calculates a new priority at next boot.
Force Recalculation of the Cache
If you do not want to wait for system start changes, simply delete the pack-file with
sudo rm /var/lib/ureadahead/pack
and the database is forced to regenerate.
The Package ureadahead should be installed since Ubuntu Lucid. In order that über-readahead hears about your favorite applications you want to cache, you have to run them instantly after login!
But my System Startup is slower now!
The first calculation and the one after each system start change certainly leads to a slowdown of the whole process. The future ones though should reduce the time for both the boot and the program start.