Tested on Ubuntu Linux 6.04 (Dapper)
originally posted at: http://howtoforums.net/viewtopic.php?t=12

Summary:
apt-get install bootchart
apt-get install bum
reboot
mkdir ~/bootchart
cp -v /var/log/bootchart/*.png ~/bootchart
file browse to ~/bootchart
view the results with an image viewer
optimize afterwards using /usr/bin/bum


Then if you are lazy you can automate it by copying this into a shell:
Code:
echo "
#!/bin/bash
# run BUM to reduce Boot Time
# apt-get install bum if you do not have it
# /usr/bin/bum
cp -v /var/log/bootchart/*.png ~/bootchart" >~/bootchart/copychart.sh
next time just run:
Code:
sh ~/bootchart/copychart.sh
*You could also symlink this to a boot script and a web server if you are running apache for example:
To Symlink to a runlevel so that you can view your bootchart the next time you boot copy this into a shell:
Code:
sudo ln -s /home/${USER}/bootchart/copychart.sh /etc/rcS.d/S99bootchart
chmod 770 /home/${USER}/bootchart/copychart.sh
To Symlink to apache (tested with apache 1.3.34)
Code:
sudo ln -s /home/${USER}/bootchart/ /var/www/bootchart
Then you should be able to browse to http://localhost/bootchart

reference: thanks to christooss:
http://www.ahacic.5gigs.com/blog/?p=21

enjoy !