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From: lkoop@pnet01.cts.com (Lamonte Koop)
Newsgroups: comp.sys.amiga.tech
Subject: stopping multitasking
Message-ID: <4440@crash.cts.com>
Date: 16 Sep 90 22:16:08 GMT
Sender: root@crash.cts.com
Organization: People-Net [pnet01], El Cajon CA
Lines: 26

I have a question relating to the use of the system call Forbid() and
Disable()...I am currently writing a benchmarking program which implements
several common benchmarks used to time system performance (complete with full
intuition interface!)...ok, here's the question:  I have an option in the
program's menu to enable a user to disable the multitaking in the system to
get more accurate timing results...unfortunately, I've discovered some, shall
I say interesting, things about both forbid() and disable().  If the program
uses just forbid(), the timing results for certain tests are slower than if
just disable() is called...however, if BOTH forbid() and disable() [I just
wanted to see the effect] are called, some tests (particularly a version of
the WritePixel test first introduced by CSA) are FASTER, whilst others (my
Sieve test) are SLOWER than with just one of the calls made....and not by jsut
tiny amounts...by a second or so. [other tests differ in performance by
smaller amounts].  I know the confusion I have here is based on a
misunderstanding of these functions, so could someone kindly give me a clue as
to what's up here? Also, what would be the best function of these two to use
for the most accurate results?  

Thanks in advance:
---LaMonte

"The most original .sig file yet...a non-existant one..."

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