Warp wrote:
> scott <sco### [at] scottcom> wrote:
>> In Windows you just install a driver, why do you need to recompile the 
>> kernel?
> 
>   It's the classical monolithic kernel vs. microkernel war. There are
> advantages and disadvantages in both methods.

I don't think Windows is anywhere near what you'd call a "microkernel", 
altho it looks like MS is trying to push everything they can out of kernel 
space for their own protection.

Generally a "microkernel" runs as little as possible in kernel space, 
deferring all device drivers and such to user-space code, providing only 
things like scheduling and IPC.  (MS's Singularity, Amiga's original OS 
(except that was *all* kernel mode), Mach (about which I know almost 
nothing), etc.)

When a device driver can't crash the system any harder than user code can, 
it's a microkernel. :-)

>   When the driver is integrated into the kernel, like in linux, it will
> obviously always work even if the kernel is seriously updated (because
> all the embedded drivers will be updated for the new kernel design as
> well).

I don't think that obviously follows. If nobody updates the driver, it'll 
break (or more likely just not be present) in newer kernels. Having the 
sources available of course lets you fix it, if it's worthwhile to whoever 
is competent to fix it. I.e., it's not that the kernel is monolithic, but 
that the sources are available to do the fixing, that keeps drivers running 
under Linux. (Actually, I've seen many complaints that the kernel doesn't 
provide a stable platform for drivers, and it slows development to have to 
fix every driver with repeated kernel changes that break them.)

-- 
   Darren New, San Diego CA, USA (PST)
   The NFL should go international. I'd pay to
   see the Detroit Lions vs the Roman Catholics.

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