Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!cs.utexas.edu!yale!cs.yale.edu!fischer-michael From: fischer-michael@CS.YALE.EDU (Michael Fischer) Newsgroups: comp.sys.atari.st Subject: Re: RateHD Message-ID: <16969@cs.yale.edu> Date: 24 Feb 90 15:11:49 GMT References: <900223121113.363135@DMZRZU71-UNI-MAINZ--GERMANY> Sender: news@cs.yale.edu Reply-To: fischer-michael@CS.YALE.EDU (Michael Fischer) Organization: Yale University Computer Science Dept, New Haven CT 06520-2158 Lines: 28 In article <900223121113.363135@DMZRZU71-UNI-MAINZ--GERMANY> Ritzert@DMZRZU71.BITNET writes: >Chris Ridd wrote: > >>I tried the RateHD a day or so ago >>... >>time was only about 36ms! Has DLII (the defragger used) done something >>unexpected to my drive, or has RateHD gone doolally? > >RateHD is buggy. The results for the access time can be considered only >a *rough* estimate. I found out that there is even a dependence on the >partition size. > Access time is seek time plus rotational delay. I don't know exactly what RadtHD is measuring, but the larger the partition, the further the head has to move to get from one end of the partition to the other, so it only stands to reason that the average access time should increase. This is hardly a reason to call a program buggy. This only points out the fact that overall disk performance can't be adequately measured by a single number -- it's very dependent on exactly what you are doing. RateHD measures the disk under one set of assumptions. Your mileage may vary. ================================================== | Michael Fischer | | Arpanet: | | Bitnet: | | UUCP: | ==================================================