Slow grub boot when /boot/grub is not on first partition

[Simon Wagner]

Hello dear GRUB2 developers,

I am a user of Ubuntu 9.10, which uses GRUB2 1.97. Unfortunately GRUB 
needs a rather long time loading the modules. For 2 minutes or so it 
just displays "GRUB loading..." until the boot menu is shown and I can 
start Ubuntu.

The bug has already been reported at Launchpad: 
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/420933

I tried to find out what causes the problem. I have the following disk 
layout:

A "Windows HD" with the following partitions
/dev/sda1
/dev/sda2
/dev/sda3
/dev/sda4
/dev/sda5

A "Ubuntu HD":
/dev/sdb2 (Extended Partition)
/dev/sdb5 (swap)
/dev/sdb6 (small partition, holds some misc data)
/dev/sdb7 (Ubuntu 9.10)
/dev/sdb8 (Backup)

So when I add
   set debug="disk"
at grub.cfg I can see grub accessing the disk. It cycles through all the 
partitions, then reads data from sdb7, cycles again through the 
partitions, reads again from sdb7, and so on...

I can't really tell whats causing this, I used the Ubuntu 9.04 package 
of grub2 before and that had not this problem. The package dates back to 
to the grub2 version from the 24th July of 2008.

Maybe it is possible to do some caching in GRUB2? So for example, if
   search -u someuuid
is done, the result is saved, and if we do that again, we can lookup in 
the cache which drive has that uuid? The same for the FS type. If we 
once did detect ext2 on hd1,7 we should cache that, so we don't need to 
detect that again.

I will try to add more grub_dprintf calls, so that I can better see what 
is going on.

Sincerly
Simon W.