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From: dave@westmark.WESTMARK.COM (Dave Levenson)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Re: Strange problem with Landmark speed test
Message-ID: <2200@westmark.WESTMARK.COM>
Date: 30 Dec 90 05:30:30 GMT
References: <5157@husc6.harvard.edu>
Organization: Westmark, Inc., Warren, NJ, USA
Lines: 23

In article <5157@husc6.harvard.edu>, albert@endor.uucp (David Albert) writes:
> I'm running MS-DOS 4.01 on a 25Mhz AMI '386.  When I run the Landmark
> cpu-speed test (the one with the bar that graphically compares the
> speed of the processor to the speed of a 4.77Mhz PC and a 6Mhz AT)
> the value I get depends on how many TSRs are loaded -- but not
> monotonically.  The value I get is either 25 (approx) or 17 (approx)
> and changes from one to the other as I load TSRs.  Some TSRs cause
> the change, some don't.  Any idea what's going on?


I would guess that one or more of your TSRs is hooking the clock
interrupt, and stealing some of your CPU time on every tick.  I
think this interrupt occurs about 18,000 times per second, so even
if the TSR is only looking at its work queue and deciding to do
nothing, it does a lot of that.  I'm not familiar with the internals
of the Landmark test, but it may use the clock-tick itself, and
there may be some contention for it.

-- 
Dave Levenson			Internet: dave@westmark.com
Westmark, Inc.			UUCP: {uunet | rutgers | att}!westmark!dave
Warren, NJ, USA			AT&T Mail: !westmark!dave
[The Man in the Mooney]		Voice: 908 647 0900  Fax: 908 647 6857