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Re: Lua as a scripting language in NetBSD

Joerg Sonnenberger <> writes:

> On Mon, Oct 19, 2009 at 10:05:13AM -0400, der Mouse wrote:
>> >>> The memory requirements are actually low, 64K RAM per state.
>> >> That doesn't strike me as all that low, in the kernel.
>> > I understand where you're coming from, but these days that kind of
>> > overhead fits in the Unix kernel on cellphones.
>> Has NetBSD lost its interest in running on old or otherwise constrained
>> hardware, then?  I know lots of machines - I even own some - where 64K
>> of overhead in the kernel is nontrivial.
> I think the 64KB RAM is the amount for an active VM. Consider it
> logically equivalent to a kernel thread. Compare that to the size of a
> uarea (12KB on my system) and it is not huge. E.g. for the use as a
> packet filter it can sanely be limited to one state per CPU. It still
> remains an optional feature.

I'm sure that Forth fits even more strict constraints.
64K per VM is more than enough, 8K is achieved really easily. And if you
allow some assumptions, 4K per "thread" isn't hard either.

If you have FreeBSD, you can find FICL source in /usr/src/sys/boot/ficl.


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