🚀 go-pugleaf

>bakraa@engin.umich.edu (Sriram Swaminarayan) wrote:
>
>>In article <3169a538.59264276@news.ucla.edu>,
>>Andrew Chiang <andrewc@seas.ucla.edu> wrote:
>>>On 8 Apr 1996 14:45:28 GMT, <102425.2720@compuserve.com> wrote:
>>>
>>>>
>>>>
>>>>Performance:  ZIP performs closer to the speed of a floppy than a hard disk.
>>>>
>>>I would disagree with that...  Perhaps you're referring to the
>>>parallel port version.  The SCSI version while definitely no where
>>>near the speed of a hard drive, is at the same time not even NEARLY as
>>>slow as floppy...  I would say it's at least 4-6 times faster than
>>>floppy...
>>
>>The access time on the Zip drive is ~26mS.  I think this
>>is independent of whether it is SCSI or parallel.  The 
>>interface just determines how fast you can move data off
>>of the drive (I think, and I'm probably wrong)
>>
>>--Sriram
>>
>>

Yes, but what is the access speed of a floppy.  Just as a
thumbnail comparison using my Mark 5 calibrated wristwatch
I copied 8 files totalling 1.23MB from my Maxtor 540A drive
to a) a SCSI Zip drive, b) a floppy, c) a DEC RZ73.

              Zip     Floppy    RZ73
              ---     -----     ----
Time in secs: 8.43    96.60     5.39

Let's see, is the Zip closer to the floppy with a delta of 88.17 secs
or to a hard disk drive with a delta of 3.04 secs?  Shall we do
percents?  The RZ73 is 36% faster than the Zip.  The Floppy is
1049% slower.  Are we clear yet that a SCSI Zip is not a floppy?

How about some more data,
the Adaptec EZSCSI benchmarking program gives (for 64K blocks)
a transfer rate of (it doesn't do floppies):

              Zip     RZ73
Sequential:   910     1980   K/Sec
Random:       630     1165   K/Sec

Yes, the RZ73 is about twice as fast by these measures, floppies, however,
aren't even in the same league.  You can compare the Zip to the drives
from a four-five years back that were quite widely used which had 28ms
access and probably similar transfer rates.  A floppy? I don't think so,
not unless you are talking about what a Zip cartridge looks like.

Now the parallel port version may be a whole different story, but then
you aren't comparing the speed of drives anymore, you are comparing
the speed one is able to shove through the parallel port on any
given machine.  While this is perhaps an interesting data point, it isn't
very useful for comparison purposes.  In general I would
say that if it is desired to get near the performance that a Zip
is capable of you need a real SCSI adaptor.  This is hardly unique
to the Zip, however, I would also say that in general, devices that plug
into parallel ports will perform poorly compared to those that
use a card that plugs into the machine providing a more
high performance interface.  I have an Trantor MiniSCSI EPP
parallel -> SCSI adaptor which when plugged into real hard drives
from the parallel port of an Aero never did better than around
130K/s transfer rates.  Pretty pitiful compared to the performance
of the New Media Bus Toaster PCMCIA card I replaced it with.

David Albrecht