Replacing rc(8) (Was: FreeBSD Boot Times)

[Wojciech Puchar]

> replacing rc.d, since that's almost certainly not relevant to the
> original topic of improving the overall boot time.

indeed.

>
> If you analyze the boot process thoroughly you should see that out of
> the total time taken to boot, nearly 0 is spent by rc.d actually doing
> something. Almost all of the actual time is spent waiting for other
> stuff, either the kernel (primarily) or the services that the system is
> running actually starting up.
>
most of boot time consist of

- delay in bootloader. setting autoboot_delay can partially delay it, 
delay to zero can be achieved by patching first stage booter that too add 
delay

- delay in kernel initialization. making custom kernel helps of course but 
still it takes eg 10 seconds on my laptop. putting things that are not 
needed instantly at boot - as module - may help. USB being prime example.

- delay at rc.d scripts - there are some delays inserted.

> The latter item is the only place where making changes to rc.d is going
> to help, and only then by parellelizing, and even then you are not
> really going to gain much since most things at boot time are serial.

grep sleep /etc/rc.d/* usr/local/etc/rc.d/*

>
> So while talk of how to get your favorite boot-time manager into FreeBSD
> may be entertaining, it's not likely to be productive, and almost

it is unimportant as FreeBSD don't crash.