On Fri, Aug 06, 1999 at 03:57:59PM +0000, Richard Adams wrote:
> >
> > On Fri, Aug 06, 1999 at 01:51:30PM +0000, Richard Adams wrote:
> > > > Erm.. where's the speed advantage come from? How does making the
> > > > kernel smaller speed it up?
> > >
> > > The speed advantage is because the "_biggest and best advantage_" of kernel
> > > modules is memory usage, the smaller the kernel the more memory below 640K
> > > that gets freed at bootime.
> >
> > Yerk. I thought we didn't need to bother with that? Is this where you
> > have to copy a chunk of ram below 640k to execute it? I'd like a clear
> > explanation if one is possible.
>
> Dont misunderstand me, the kernel itself does not have all the dos
> limitations, however what i said was the more memory below 640k the faster
> the kernel is because it has more memory space.
This is not making much sense to me. Even the smallest kernel I ever made
(the lilo image was about 350) was over 640 uncompressed. this seems to imply
that linux doesn't bother with the 640k limit and as such what you say
makes no sense. What's the big deal with 640k as far as linux is concerned?
> > > However no one has mentioned another very important thing with makeing a
> > > On another note, using Redhat 6.0 for my example, the kernel 2.2.5-15 which
> > > is supplied is very small in itself, it has just about all kernel-modules
> > > one could want, execpt for Radio hams, but thats another story.
> >
> > And it's STILL bigger then the monolithic kernel I make.
> >
> > 544 -rw------- 1 root root 552504 Aug 6 21:24 vmlinuz-2.2.11ppre4-1
> > 607 -rw-r--r-- 1 root root 617288 Apr 20 13:16 vmlinuz-2.2.5-15
> > 549 -rw-r--r-- 1 root root 557651 Aug 3 17:32 vmlinuz-2.2.7-1
> >
> > 2.2.7 and 2.2.11ppre4 are both monolithic kernels. Everything I need is
> > compiled into them. 2.2.5 is redhat's original which is mostly (and
> > frighteningly IMO ;) modular. I had a nice shock of suprise when I saw the
> > file size differences. I totally figured that my monolithic kernel
> > would be bigger then redhat's modular one...
> >
> > (This is from RedHat 6.0)
>
> What you have is a large kernel without supporting most hardware, 2.2.5-15
> on the otherhand is a little larger than your mono kernel and has support
> for a wide range of hardware. There is a big differance.
Nope. As the hawrdware 225 supports is done so through modules. As such it
shouldn't be taking up space within the main image... Now I can't remember
if IDE support is compiled in but I doubt it'd be any smaller then AHA7xxx
SCSI low-level driver, disk scsi driver and generic scsi driver combined.
> What you have made is a large kernel, however i make kernels as well, when
> one gains experiance and (most important) confidance one starts to play with
> the kernel, now i consider my kernel to be _large_, 381283k, i could get
Well 381meg IS large. :)
> that down by 60k or so and still have all i need but then in module form.
>
> What is the advantage of that, once again memory, if we were both to have
> 64M of memory we would then compare our memory with 'free'.
> Your system would use much more memory (to be seen in the Total field), mine
> uses 63668 from the 64M i have, so my kernel uses up the rest, what you
> would see is possably 62999 (just to explain a point), i hope you now see
> what i mean with memory usage and therefor a faster kernel and have general
> support for different hardware and use _less_ memory.
Erm. My hardware hasn't changed that much since the day I got my computer. I've
always required IDE support and still do. I've always required framebuffer
support and still do, same for the filesystems I have configured (dos, xt2
etc). the only thing that changed recently was the addition of a scsi card
and burner so I've added those into the kernel.
It's not like your hardware changes from one reboot to the next. The advantage
of modules with changing hardware would be if you had a fair few machines
with different hardware requireemnts. Then you just dump in the kernel and
modules, config as need be and off you go. No need to keep on recompiling.
--
CaT ([EMAIL PROTECTED]) URL: http://www.zip.com.au/dev/null
