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Date: Fri, 20 Jun 2003 00:35:46 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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cc: Marcel Moolenaar <marcel@xcllnt.net>
Subject: Re: Implementing TLS: step 1
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Julian Elischer wrote:
> The big cost is that a processin x86 can only have a limited number of
> segments set up in teh Local descriptor table (LDT).
> I forget the actual number but i vaguely remember that it is 16383 or
> 8191 or something.

65536, but it includes the recursive mapping and the call trap, etc.,
so it's reall 65531.

This is one reason we don't use the TSS for context switching,
and why Linux, which used to use the TSS, doesn't use it any
more.

-- Terry