Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!elroy.jpl.nasa.gov!ames!ames.arc.nasa.gov!lamaster
From: lamaster@ames.arc.nasa.gov (Hugh LaMaster)
Newsgroups: comp.periphs
Subject: Re: Alternate IPI disks in a Sun
Message-ID: <43941@ames.arc.nasa.gov>
Date: 1 Mar 90 01:55:52 GMT
References: <5048@emory.mathcs.emory.edu> <43841@ames.arc.nasa.gov> <10538@alice.UUCP>
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Organization: NASA - Ames Research Center
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In article <10538@alice.UUCP> andrew@alice.UUCP (Andrew Hume) writes:
>listen, if you have an ipi interface, do yourself a favour
>and get some real disks. For example, the Sabre 2HP is only
>a little more expensive than the regular sabre, a tad smaller
>but twice as fast.

I assume that you mean 6 MB/sec.  I guess Sun doesn't sell these.  Are
there any problems with drivers/formatting/etc?  Can you just plug them
in and run?

I thought the filesystem was the bottleneck.  The best you can get out
of a 3 MB/sec disk is ~2MB/sec now.  What kind of speeds can you get out
of a 6 MB/sec disk?

I believe that the maximum throughput to memory on a Sun-4/490 is 13.4MB/sec
based on the paper by Hsieh et al. in last falls IEEE Computer Design.
Do you have any insight into the aggregate
performance improvement with faster disks?

  Hugh LaMaster, m/s 233-9,  UUCP ames!lamaster
  NASA Ames Research Center  ARPA lamaster@ames.arc.nasa.gov
  Moffett Field, CA 94035     
  Phone:  (415)604-6117