Path: utzoo!utgpu!attcan!uunet!peregrine!elroy!ames!ucsd!rutgers!rochester!pt.cs.cmu.edu!cadre!pitt!darth!apexepa!gary
From: gary@apexepa.UUCP (Gary Wisniewski)
Newsgroups: comp.sys.ibm.pc
Subject: Re: IBM PS/2 70 vs MAC II
Summary: I-O speed IS better with PC
Message-ID: <342@apexepa.UUCP>
Date: 9 Sep 88 12:36:36 GMT
References: <8X7VPiyS2k-0M0m1wg@andrew.cmu.edu> <12292@cisunx.UUCP> <5489@pasteur.Berkeley.EDU>
Reply-To: gary@apexepa.UUCP (Gary Wisniewski)
Organization: Apex Software Corp., Pittsburgh, Pa.
Lines: 23

In article <5489@pasteur.Berkeley.EDU> woan@cory.Berkeley.EDU.UUCP (Ronald S. Woan) writes:
>In article <12292@cisunx.UUCP> goosh@unix.cis.pittsburgh.edu (Walter Perz) writes:
> ...
>>when you consider speed, remember that the whole ibm family generally
>>smokes the macintosh at i/o.... and that is what you notice the most.
>
>This is a bunch of baloney, the SCSI drives that most Mac's are attached to
>will smoke our MFM drives. What really determines speed is how much you
>are willing to spend.
> ...

Walter is correct---the Mac (even Mac II) is slower at I-O.  Although the
SCSI interface and drives are faster, all Macs lack DMA capability.  Thus,
any PC with a fast MFM drive will beat the Mac.  This problem extends to
high-bandwidth network products as well.  Ethernet boards have bandwidth
limitations on the Mac since they can't do DMA.

We're designing a database product for the Mac, and the I-O speed difference
is a major design concern.

-- 
Gary J. Wisniewski				  Apex Software Corporation
{allegra,bellcore,cadre}!pitt!darth!apexepa!gary  Phone: (412) 681-4343