To:	djgpp AT sun DOT soe DOT clarkson DOT edu
From:	LIP AT odie DOT ee DOT wits DOT ac DOT za
Date:	1 Jul 93 10:49:50 SAT
Subject:	efficiency: DPMI vs VCPI

Hi,

Has anybody benchmarked the speed of a DJGPP 1.10+ program running
under VCPI and DPMI to gauge the relative efficiency of the two
techniques?  The author of a PD app. built using the Intel 386/486
code builder that I evaluated recently, claimed that his DPMI version
was ~1.5x faster than the VCPI version. Any comments?

Secondly, the FAQ for DJGPP states (if I understand it correctly) that
up to 128 Mb of memory and 128 Mb of virtual memory can be allocated
giving a grand total of 256 Mb.  Is this a theoretical calculation or
has this actually been tested and verified?  What was the PC setup
that was used during the testing/verification (mem manager, config.sys
and autoexec.bat)?

Thirdly, if I remember correctly, a recent Computer Langauge issue
(June?) reviewed GCC (not quite DJGPP) along with several other major
league C/C++ compilers.  It would be good to see a good comparative
study of DJGPP, EMX, Microsoft C, Watcom C, Borland/Turbo, Zortech
etc.

Regards,
Tony.

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