[LinuxBIOS] Rapid booting of Linux -- Recommended distributions / Kernel options?

[Eric Poulsen]

I've been using Ubuntu (because of ease of install / familiarity with 
Debian) as my test platform for rapid booting.  Ubuntu is remarkably 
slow at booting -- It's made to work with just about any hardware.  Can 
anyone recommend any distributions that are more geared towards the 
embedded rapid-boot?  Essentially, I'd like to have a user-space program 
that's doing I/O via serial / usb to do data logging as quickly as 
possible, and everything else (display, mounting a mechanical hard 
drive) can wait.  Essentially, steps 1-3 have to be as fast as possible.

1) LB + Filo -- Load Kernel from CF
2) Kernel init (I have this down to 0.9 seconds)
3) User space program that loads USB drivers and begins data logging
4) Everything else: network, display (X.org), hard drive mount etc

I need a distro that lets you do most of the usual startup stuff later.

---

Here's a list of kernel options that I'm using -- anybody have any other 
"tricks" to speed this up?

root=/dev/hda1
console=ttyS0,115200 [I know this slows it down]
console=tty0 [This might be a major time waster, also -- I suspect the 
kernel VGA init is slow]
lpj=2136847
dhash_entries=16000 [I'm not sure if making the Dentry hash is slow, or 
if the VGA init routine just before it is the culprit]
ide0=0x1f0,0x3f6,14
ide0=noprobe
ide1=noprobe 
ide2=noprobe
ide3=noprobe
ide4=noprobe
ide5=noprobe
hda=65535,16,63
hdb=none
hdc=noprobe [This is the CF -- don't need it after boot]
hdd=none
no_hlt

Also, If I do hda=noprobe, I guess the kernel won't mount it, so it 
fails.  Seems like the kernel *must* probe the hd?  I thought as long as 
it has the CHS, it didn't need to probe.