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From: c60c-1gd@e260-1c.berkeley.edu (Joon Song)
Newsgroups: comp.sys.amiga.hardware
Subject: Hard disk transfer rates
Summary: SCSI
Message-ID: <1990Sep1.231510.10650@agate.berkeley.edu>
Date: 1 Sep 90 23:15:10 GMT
Sender: usenet@agate.berkeley.edu (USENET Administrator)
Reply-To: c60c-1gd@e260-1c (Joon Song)
Organization: University of California, Berkeley
Lines: 15

I'm sorry if this has been discussed before.  I've read several articles
claiming that hard disk transfer rates through a SCSI port is as high as
3.5 meg/sec.  Is this the actual throughput of the hard disk system?  
Does this involve data being cached?  3.5 meg/sec is considerably faster
than what I had thought possible for hard disk r/w.

Suppose a hard disk had 34 sectors/track.  A hard disk spins 60 rev/sec.
So the fastest disk transfer rate should be:
    34 sectors/track * 512 bytes/sector * 60 rev/sec = approx. 1 meg/sec.

Can someone explain how 3.5 meg/sec transfer rate can be possible?

---------
Joon Song
c60c-1gd@web.berkeley.edu