Re: Max # of processes?

Andrew E. Mileski (aem@aem.ott.hookup.net)
Tue, 10 Sep 1996 18:40:10 -0400 (EDT)

> > Well, on x86 architecture:
> > My guess is: ( 16384 - 8 ) >> 1 = 8188
> > If APM is enabled: ( 16384 - 11 ) >> 1 = 8186
> >
> > The limit is the global descriptor table (GDT). It can hold 8191
> > descriptors (selectors are 14 bits, and 0 is reserved by the CPU).

Doh! I screwed up. Sorry.

Selectors (16-bits) have a 2-bit privledge level, and 1 bit that
says the descriptor is in the GDT or LDT. Like I said, there are
8191 descriptors <- I should have read what I wrote!

Max NR_TASKS on x86 architecture:
My new guess is: ( 8192 - 8 ) >> 1 = 4092
If APM is enabled: ( 8192 - 11 ) >> 1 = 4090

Besides, the GDTR has only a 16-bit limit (each descriptor is 8 bytes).

--
Andrew E. Mileski
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