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From: dmurdoch@watstat.waterloo.edu (Duncan Murdoch)
Newsgroups: comp.sys.ibm.pc
Subject: Cache hit counter wanted
Message-ID: <1641@maytag.waterloo.edu>
Date: 5 Mar 90 16:05:24 GMT
Sender: daemon@maytag.waterloo.edu
Reply-To: dmurdoch@watstat.waterloo.edu (Duncan Murdoch)
Organization: U. of Waterloo, Ontario
Lines: 21


I'd like to measure the performance of a couple of disk cache programs in real
use.  The obvious measurement as to how well they're performing is the number
of cache hits versus misses; however, neither of them keeps track.  (I've got
MS SMARTDRV.SYS and Mace MCACH-EM.SYS.  According to the near-useless test
supplied by Mace, they're about equal.  But who cares how long it takes to
read a long file backwards?)  

It would seem straightforward enough to write:  I'd install a TSR or device
driver before the cache program that kept count of BIOS disk read requests,
and another copy after the cache.  The difference in the two counts would
tell me how many requests had been satisfied from the cache.

Does anyone know of an already existing program to do this?  If not, can you
see any obvious flaws in the "design" given above?

Please reply either by email or by posting here; I'll summarize any information
I get by email that doesn't appear in a posting.

Duncan Murdoch
dmurdoch@watstat.waterloo.edu