[openbeos] Re: couple o'things
- From: Michael Noisternig <michael.noisternig@xxxxxxxxx>
- To: openbeos@xxxxxxxxxxxxx
- Date: Sat, 25 Aug 2001 23:48:07 +0200
> > > On the kernel timing thing, I do not think NewOS comes really close
> > yet, but then again,
> > > it has no AMD/MMX/3DNow optimalisations as far as I know, so that is a
> > major
> > > (performance) drawback on most (modern) machines....
I do not quite understand what you mean with kernel timing thing. I
don't think it's too slow (without having tested it). MMX/3DNow code is
hardly useful here (except in special cases like memcpy - see below).
Performance issues come last, we would all be happy to get *any* working
kernel at first.
> >b) i don't think BeOS kernel has any SIMD optimizations aside from an mmx
> >memcpy.
> >but we need to ask Daniel about that.
>
> I can tell you looking at the disasm of the kernel that they use a special
> instruction (not even recognized by the disasm unit of objdump) for doing a
> fast ring 0 gate return back into userspace for some Intel/AMD chips....
> You can even see this looking at the symbol dump that objdump can give
> you.... They're pretty bleeding obviously called fast_ xxx slow_xxxx
> xxxx_amd, or any other variant you can think of :) Using objdump helps,
> really :)
These fastest version functions can be found in all MMX/3DNow developer
manuals and can be easily integrated in our kernel.
> >as about reference docs,
> >
> > >Are we actually going to use doxygen? And if so, are we going to make a
> > universal style
> > >in how to document the methods / functions / classes / etc? We probably
> > need to decide
> > >this before we all start coding like crazy....
I'd definitely vote for a documenting system. Heard that doxygen is
quite good.
Michael.
- References:
- [openbeos] Re: couple o'things
- From: Ithamar R. Adema
Other related posts:
- » [openbeos] couple o'things
- » [openbeos] Re: couple o'things
- » [openbeos] Re: couple o'things
- » [openbeos] Re: couple o'things
- [openbeos] Re: couple o'things
- From: Ithamar R. Adema