On Wed, Jan 05, 2005 at 04:30:05PM -0000, Leigh Brown wrote: > Sven Luther said: > > On Wed, Jan 05, 2005 at 09:45:13AM -0600, Hollis Blanchard wrote: > >> On Jan 5, 2005, at 5:47 AM, Sven Luther wrote: > >> >On Wed, Jan 05, 2005 at 10:49:19AM +0100, Philippe Guyot wrote: > >> >>>BTW, i have another question. I am trying to fix debian-installer > >> >>>to create the prep partition, but i would like to have some info > >> >>>on the expected constraints of said partition. Some tell it has > >> >>>to be entirely in the first 8MB, others the first 5MB, and my > >> >>>powerstack has a 17MB boot partition right now. > >> >> > >> >>All I can say, it's that my boot PReP partition is the 1st and about > >> >>4 MB in size (cannot size it less than 1% of the disk.....) > >> >>second partition is / > >> >>third is swap. > >> > > >> >BTW, for debian, it makes more sense to have the second partition > >> >as swap, and the third as /, i think, since it was decided some > >> >time back to default to root=/dev/sda3, and not sda2. > >> > > >> >>That works for me. > >> > > >> >Until the kernel grows beyond 4MB. > >> > >> The size of that partition depends on firmware limitations. I have > >> definitely seen reports of systems not booting when the PReP boot > >> partition was too large. I think on some systems that has even happened > >> at 8MB. > > > > Is the problem really the size of the partition, or the space used by > > the kernel. I mean we could make a 100MB partition at start, and since > > we just dd the kernel to it, the kernel would be found at the start of > > the partition, and the firmware probably doesn't care about the real > > size of the partition, as long as it can access all the kernel data we > > added to it, no ? > > > > Do we have some documentation of the firmware limitations ? > > > >> In other words, should you need more space than 4-5MB at some point in > >> the future, you cannot simply make a bigger boot partition. > > > > 8MB would be good, 4-5MB only would probably be a bit just. > > Surely if you make the default mkinitrd behaviour a bit more sensible > there won't be a problem. A compressed 2.6 kernel is about 1.5MB, and
The compressed kernel should be arounf 1.0MB only. > an initrd using MODULES=dep is about 1.5MB, which makes about 3MB, > giving a comfortable amount of space for future growth... well, when i use MODULES=dep, i still get all the filesystem and a bunch of extra ide drivers, so it is no less than 4MB. Mmm, you are right about this one, it is only 1499136 now, which makes a total of 2856844, quite reasonable. Mmm, i wonder it may even boot on the pegasos 1 with the broken OF now. Still, partman-prep is currently written to make sure the prep partition is in the first 8MB. Friendly, Sven Luther
