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From: solworth@uicbert.eecs.uic.edu (Jon Solworth)
Newsgroups: comp.os.research
Subject: Re: Extremely Fast File Systems
Message-ID: <5494@darkstar.ucsc.edu>
Date: 27 Jul 90 00:36:46 GMT
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Saving a gigabit/second to disk is going to take a lot of disks.
If a disk can write at 6 MB/sec, the 20 disks are needed just
to accept at network speeds (this assumes that the disks are essentially
doing a totally sequential access).

Add in any kind of random seeks, and the number of disks can skyrocket.
In addition to Berkeley RAID and Sprite projects (which essentially
use disk arrays as striped disks), disk caching of writes is an
alternative way of getting near sequential access rates.

(C. Orji and I have a paper in the 1990 Sigmod entitled
"Write-only disk caching")


Jon Solworth
UIC