[rescue] Sunburst

[nate at portents.com]

On Fri, 21 May 2010 12:02:11 -0400 (EDT), adh at an.bradford.ma.us (Sandwich
Maker) wrote:
> " From: gsm at mendelson.com
> " 
> " []
> " 
> " In some ways I'm surprised by MacOS, the Leopard scheduler degrades
> nicely
> " under load, even though it was designed for a single user workstation.
> 
> did apple actually write it themselves, or did they inherit it with
> the mach microkernel?  that would have roots in big iron.

Avie Tevanian, former head of software at NeXT, Chief Software Technology
Officer at Apple until 2006, was one of the original authors of the Mach
kernel at CMU.  However what Apple evolved from the Mach kernel isn't
really the quite the Mach kernel anymore, it's really the XNU kernel,
because it's changed significantly in some ways.  (If I were to take a stab
at one of the reasons OS X degrades gracefully under pressure, the I/O Kit
driver architecture is probably a significant contributor, and is unique to
the XNU kernel among operating systems.)  You can read more here:

http://osxbook.com/book/bonus/ancient/whatismacosx//arch_xnu.html

and there's a talk here:

http://chaosradio.ccc.de/24c3_m4v_2303.html

- Nate