Re: [OT] speeding boot process (was Re: [ANNOUNCE] hotplug-ng 001 release)

Bernd Petrovitsch
2005-02-15T13:51:21Z

On Tue, 2005-02-15 at 14:20 +0100, Helge Hafting wrote:
> Bernd Petrovitsch wrote:
> >On Tue, 2005-02-15 at 09:55 +0100, Helge Hafting wrote:
[...]
> >These are not dependencies but "only" the sequence of startup (and it is
> >not only Debian but also Fedora/RedHat, SuSE, Mandrake and probably all
> >except Gentoo).
> >
> Yes, it is a sequence. It it derived from real dependencies though,
> where nondependent stuff have the same number.

Yes, of course. Sorry if that wasn't clear.

> >However for real dependencies and parallelism you want the info similar
> >to creat a Makefile from it (i.e. the explicit dependency from service X
> >to service Y). As a consequence you can get rid of the numbers (since
> >they are not needed any more).
> >
> Now that is a really good idea. Init could simply run "make -j init2" to

Actually I just used it to illustrate the idea.
As with Gentoo, I'm not a guru there so other people must comment if
Gentoo actually starts services in parallel.

> enter runlevel 2. A suitable makefile would list all dependencies, and
> of course the targets needed for "init2", "init3" and so on.
>
> It might not be that much work either. Parallel make exists already,
> and the
> first attempt at a makefile could simply implement the current sequence that
> is known to work. Then the tweaking comes. :-)

You just have to cope with the potentially parallel output reliably
especially in error cases (which is IMHO basically the most work).

Bernd
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