Slow Kernel Decompress

This was already posted to the laptop forum and bumped once, but I've gotten no response. I'm hoping someone here may be able to help.


===================================

What I'm running:
- Kernel 2.6.7 (working good - about 1.8MB [ a little fat ] )
- Slack 10.0

on an IBM A21m ThinkPad. 750Mz - 192MB - RAM - 40GB (4200RPM) HDD

Everything is working extremely well, finished tweaking the kernel to just how I want it. And it just struck me this morning (I have no idea why it took me this long to notice) that my kernel takes about 20 seconds to decompress. I have a desktop running essencially the same setup, but the same size and version kernel decompresses in about 1.5-2 seconds, right about how long it should take.

My first guess is that my hard drive is causing the delay. I retweaked all the power settings in BIOS, still no change. When I select my kernel in lilo, my hard drive flashes for a milisecond (accessing the kernel image, i'm guessing) and then starts decompressing, sssslllooowwwlllyyyy. So it's not the hard drive, well, I'm pretty sure.

I considered setting up GRUB, but LILO is working just fine in my multi-boot setup on my laptop and desktop. And LILO isn't causing this hang-up on my desktop.


If it wasn't for this hang-up on the decompression of the kernel, my notebook would be booting in about 40 seconds.


Any ideas?

Well, on my X31 I attributed the delay to the BIOS check at the beginning of boot, not decompressing the kernel. It does seem exceptionally long compared to the desktops but I figured it was just the nature of the hardware or the BIOS. I would like to see a solution
to speed this up as well, but it is not that big a deal to me.

Oh yeah, my X31 is a 1.4 GHZ Pentium-M with a 40gb 5400RPM drive and 1.5GB of RAM.

(Woo hoo!! 200 posts... O And it only took me 2 years.)

Originally posted by chasingmytail When I select my kernel in lilo, my hard drive flashes for a milisecond (accessing the kernel image, i'm guessing) and then starts decompressing, sssslllooowwwlllyyyy. So it's not the hard drive, well, I'm pretty sure.

Try using the COMPACT option in LILO. Just write compact on a line of its own toward the start of /etc/lilo.conf. That may work.

Thank's, works great! The kernel now loads almost immediately! I hope you don't mind if I copy/paste this solution into the laptop forum (credit given of course!)


I have never seen this option COMPACT before, so naturally I Google'd it and here's a compiled explanation as to why it speeds things up, for those who are curious as to why this works exceptionally well (for me anyways):

The compact option makes LILO read the hard drive faster. It merges read requests for adjacent sectors into a single read request, which reduces the load time and also makes the map smaller. This option can cause older systems to hang and may cause problems for those using LBA32 drive's.



Well, I'm happy now!

Is this option available only for laptops ? And would it save a lot of time for "regular" LILO users (i.e. those not having problems with boot time) ?

It's a normal LILO option that should work on just about any machine. It's actually recommended for use with boot diskettes to speed the boot-up process. Strangely, from my searchings, this isn't a well documented option ...

I only needed it for my laptop, lilo on my pc was fast anyways.

Yeah, but you know, speed is like candy. There's no such thing as too much candy.

Once I realised that compact speeded up the kernel loading I tried it on the pc and I lost the little line of dots that spread across the screen. So I switched back for the dot-eye-candy.