Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!crdgw1!uunet!jwt!john
From: john@jwt.UUCP (John Temples)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: IDE drives: good or evil?
Message-ID: <1991Mar28.042102.14723@jwt.UUCP>
Date: 28 Mar 91 04:21:02 GMT
References: <12070002@hplvec.LVLD.HP.COM> <1991Mar24.173308.3337@jwt.UUCP> <1991Mar25.165950.14531@santra.uucp>
Organization: Private System -- Orlando, FL
Lines: 16

In article <1991Mar25.165950.14531@santra.uucp> mstr@vipunen.hut.fi (Markus Strand) writes:
>I use on my harddisks tools which compress the disk so the data is continuos,
>so IDE-drive's cache is just what I need.

A cache is only useful if you're reading data which is already in the
cache.  If you're reading continuous data, it's not going to be in the
cache.

>When do you need to read 10M at a time. No programs need that much data.

I didn't mean to imply that my application mix typically read 10M at a
time.  I meant that reading 10M of contiguous data should defeat any
cache and show you what the transfer rate of data *from the disk* is,
not *from the cache*.  Can 64K of disk cache really help that much?
-- 
John W. Temples -- john@jwt.UUCP (uunet!jwt!john)