Date: Thu, 2 Mar 2000 11:19:42 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Kalum Somaratna aka Grendel <kalum AT crosswinds DOT net>
cc: djgpp AT delorie DOT com
Subject: Re: Fastest bitblt?
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On Wed, 1 Mar 2000, Kalum Somaratna aka Grendel wrote:

> Say there is a interrupt
> handler which is called 100 times per sec. And say that there is only one
> call to movedata in the interrupt handler. That would mean that a total of
> 100 calls to move data per sec. so imagine the overhead of setting up even
> the segregs repetetively.

First, movedata is for copying large buffers, and such things
shouldn't be done in an interrupt handler.

And second, even on a 486, loading a segment register takes 9 cycles
in protected mode.  Compared to the time to actually move the data,
this is nil.

> surely no one can say that nearptrs are slower than farptrs.

They aren't slower, but they aren't significantly faster, either.  So
using them is usually a bad tradeoff.