Re: CVS commit: src/distrib/common/bootimage

[David Brownlee <abs%absd.org@localhost>]

We have #ifdef SMALL on various userland tools - iff we keep
COMPAT_BSDTTY purely for similar reasons it should probably be renamed
to make it clear its intended purpose.

For smaller systems its not just the overall image size, its also the
runtime memory used (I remember switching from mount_kernfs to dmesg
being a net space win at runtime).

Packing vax a good example of low memory system (and one easy to test
on x86 hardware in simh) it would be interesting to see the difference
in both image size and available memory once booted between
COMPAT_BSDPTY and PTYFS+mount_ptyfs,

The runtime memory usage is probably going to be the limiting factor
long term - for for example a kernel+ramdisk floppy could be switched
to a kernel floppy and a root filesystem floppy, which could help
considerably on low ram systems at the cost of locking up a floppy
drive during install (and obviously making everything much slower :)

Maybe the answer is to so as Sun did with their Sun/386i and implement
pageable kernel text :-p


On 14 March 2015 at 13:49, Christos Zoulas <christos%zoulas.com@localhost> wrote:
> On Mar 14, 11:02am, tsutsui%ceres.dti.ne.jp@localhost (Izumi Tsutsui) wrote:
> -- Subject: Re: CVS commit: src/distrib/common/bootimage
>
> | It is a bit annoying to shrink ever growing kernels...
> | sun2 and sun3 have size restriction due to bootloader, for example.
> | (Of course I know these poor ports should retire in near future)
>
> I'll test and see the size difference on those two.
>
> | The "3. add file-system PTYFS to all the kernels"
> | seems a bit hard as we saw on PR/46812 and PR/47123
> | (we had to add ipty or opty into all MD MAKEDEV).
> |
> | I can see your reasonable goal, but we need to consider pros and cons.
> | That's all.
>
> Yes, that's why I am asking... I don't know how bad it can get.
>
> christos