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Message-ID: <001f01c18995$b8043360$1400a8c0@alex>
From: "Alex Oleynikov" <alex AT compuweigh DOT com>
To: <djgpp AT delorie DOT com>
Subject: Memory accessing performance
Date: Thu, 20 Dec 2001 15:34:27 -0500
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Reply-To: djgpp AT delorie DOT com

Hi everybody!

I've got a question related to memory accessing performance when using DPMI.
Currently I am developing an application which talks to PLCs via Modbus
protocol and I need to create a map of Modbus registers in my program.
Every register is two bytes of data and there are quite a few of them (up to
50000). First thing that comes to the mind is to use dynamic arrays of short
integers, but wouldn't it be much slower compared to 32-bit integers? (since
the compiler generates a 32-bit code which is more efficient accessing
32-bit memory locations, right?). Those registers must be updated about
every 250ms, so I'd rather sacrifice size to gain performance.

Any feedback is welcome.

Regards,
Alex