2009/4/2 Vladimir Skuratovich <skuratovich@...>:
[...]
> - For me, the startup process is slowed down considerably by mounting
>  a /home partition. The programs we'd want to start up as early as
>  possible, including X, are delayed until the mounting finishes. This
>  is especially noticeable with reiser4, as mounting it usually takes
>  a few seconds, but I suppose this is true to some extent for other
>  filesystems too. Maybe if the system has a /home partition we should
>  wait in the session manager for it to be mounted, while X is
>  starting up? Not sure what to do with other filesystems, such as
>  /usr, which still have to be mounted very early.

This would need changes to the session manager, right? Is that really
something that we want to be doing?

[...]
> - Gentoo init scripts perform a lot of 'autodetection' of different
>  system parameters. Probably the autodetection could be left as a
>  'safe boot' option, and the real values could be recorded somewhere
>  and loaded at boot time?

You'd need to add some quick sanity check for things like moving
hard-disks across hardware.

> - Instead of cleaning directories such as /var/run, they can be
>  mounted on tmpfs and the necessary directory tree inside can be
>  recreated every time.

Might there be cases where these files would be needed to analyse
crashes or for forensics?

> - Placing static device nodes on /dev while udev is starting speeds up
>  the boot significantly for me

By how much?

> With a few hours of experiments on my system I've managed to reduce
> its boot time to about ~15 seconds (not including kernel startup - and
> kernel initialization takes quite long) This is on a system with a
> 5400rpm laptop hard drive (40-45 mb/s linear read) with everything on
> LVM inside dm-crypt. It seems that the 10 second boot time for HDD
> systems, which is mentioned in Moblin presentation, is quite a
> realistic goal.

What kind of impact is dm-crypt having on your numbers?

> If someone is interested, I can post the bootchart logs somewhere.

Would be nice to look at, IMO. If you need it to be hosted somewhere,
mail them to me and I'll put them up.

> The system uses initng - but the structure of init scripts in Gentoo
> seems very similar, so I guess porting it to Gentoo would be easy.

I'm a little confused here. What system were these tests run on?

Regards,
-- 
Arun Raghavan
(http://nemesis.accosted.net)
v2sw5Chw4+5ln4pr6$OFck2ma4+9u8w3+1!m?l7+9GSCKi056
e6+9i4b8/9HTAen4+5g4/8APa2Xs8r1/2p5-8 hackerkey.com