Re: My thoughts on the "new development model"

[Bill Davidsen <davidsen@tmr.com>]

William Lee Irwin III wrote:
> On Thu, 28 Oct 2004 at 00:13:44 -0700 William Lee Irwin III wrote:
> 
>>>I'd expect vastly less than 1%, starting from the arch count, and then
>>>making some conservative guesses about drivers. Drivers probably
>>>actually take it down to far, far less than 1%.
> 
> 
> On Thu, Oct 28, 2004 at 09:04:41AM -0400, Chuck Ebbert wrote:
> 
>>  Sure, but pretty much each installation uses a different 1%.
>>  If there's a bug in there it's bound to hit someone; that's
>>what makes OS writing so difficult.  (And that's why "It works
>>for me" is not really a useful statement about the overall quality
>>of an operating system.)
> 
> 
> 99.99% of users use one arch, i386.
> 99.99% of users use one disk driver, IDE.
> The intersection of these users is probably well over 99.999% of all
> users.
> 
> Then probably a small list of secondary drivers varies. Statistically,
> users with anything but the crappiest x86 s**tboxen and a tiny subset
> of all drivers (arjan's 20) are hopelessly outnumbered.

Sorry, i386 is really a pool of Pentium, Athlon, and Opteron chips, with 
a witches brew of HT, 64bit extensions to 32 bit chips, and the like. 
Connected by a constantly changing set of Intel, SiS, VIA and other 
shipsets, and getting storage from IDE and SATA drives.

Not to mention using a vast array of CD and DVD drives and several major 
flavors of USB methods with minor variations of each, and driving their 
consoles with at least a half-dozen popular video chipsets with drivers 
of various shades of openness.

You don't even reach 99.99% with small-endian, there are more assorted 
RISC chips in use than that. I guess you're safe with twos complement 
arithmetic, although I cringed at Linus' recent "find a power of two" 
code which depends on it.  Diversity, thy name is Linux!

-- 
bill davidsen <davidsen@tmr.com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979