Re: udev sysfs docs Re: State of devfs in 2.6?

Mark Mielke
2003-12-11T02:23:52Z

On Thu, Dec 11, 2003 at 12:48:35AM +0100, Maciej Zenczykowski wrote:
> > I'm not saying module use is more memory efficient than not or vice
> > versa, but if memory usage in the 100K range is going to be the only
> > argument for autoloading/unloading of modules then it's really _not_
> > worth the effort unless someone can give that kind of support without
> > trying. Your fight for memory efficiency should start where the
> > inefficiency is the largest, and work it's way down, not the other way
> > around.
> That's not quite true - all kernel memory is statically mapped into ram
> and unswappable. 2 MB's of X will likely end up 80% swapped to disk and
> the rest is in use (and can still be swapped out when no longer needed).
> 100KB of an unused driver will not get swapped out.
> That's where the difference is. As for using small userspace? I do,
> djbdns for dns, twm for window manager etc etc...

I was under the impression, that on the x86 processors, it is not
possible to have more than ~640Kb of 'unswappable' memory. Everything
else *is* swappable.

Perhaps somebody with understanding could enlighten us on this point?

Is kernel code swappable if compiled in statically? I have assumed
that it is.

mark

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