Archive for hot plugged devices
How to Boot Linux under 5 Seconds
Arjan Van de Ven and Auke Kok the two Linux developer at Intel’s open Source Center had demonstrated booting Linux system in five seconds. They demonstrated at Asus EEE PC that had a solid state storage both developers beaten the 5 seconds time by loading 2 soft wares Fedora and Moblin. They demonstrated that in front of audience.
Now question is that how they did that? According to Arjan it starts with right attitude, that doesn’t mean booting faster, its only about booting in 5 seconds. Its better to set a time budget for whole system rather than saving seconds here and there and every step of the boot should have to be complete in allocated time. 
Nothing can be skipped while booting because Booting means making CPU and disk idle. That 5 second booting time did not include bringing up the network but that includes starting Network Manager. Arjan said that a conventional hard disk in a system take more time for start up, he has run the same load on a ThinkPad which taken 10 second time.
Fedora takes 45 seconds from power on to GNOME Display Manager log in screen. Boot Chart tool gives some details about that. In Boot chart figure 1 of Fedora boot, that figure shows the system is doing some time wasting things. It takes a whole 1-second in starting and checking the loopback device to see if all the network interfaces on the system are loopback. Then 2 seconds to start “send mail”. For that Arjan suggested for the common laptop use case that user can simply run ssmtp server instead of SMTP server, which is used only for outgoing mail.
