Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!sdcsvax!darrell
From: preston@felix.UUCP (Preston Bannister)
Newsgroups: comp.os.research
Subject: Re: optical disks
Message-ID: <4199@sdcsvax.UCSD.EDU>
Date: Wed, 28-Oct-87 15:24:52 EST
Article-I.D.: sdcsvax.4199
Posted: Wed Oct 28 15:24:52 1987
Date-Received: Sat, 31-Oct-87 15:32:23 EST
Sender: darrell@sdcsvax.UCSD.EDU
Organization: FileNet Corp., Costa Mesa, CA
Lines: 41
Approved: mod-os@sdcsvax.uucp


In article <4177@sdcsvax.UCSD.EDU> douglis@ginger.Berkeley.EDU (Fred Douglis) writes:
>It seems clear that in the long run, for a centralized archive
>service you need a jukebox with many disks rather than a small number
>of scattered small drives; however, Hugh Lauer (of Apollo) mentioned
>that he thinks it'll be a while before jukeboxes work well enough to
>use and thinks instead that people should get large numbers of small
>optical disk drives, such as one per workstation plus a few more for
>general use.

We build and sell a _lot_ of optical disk jukeboxes as a part of our
system.  They work quite well.  


As to whether to use a central jukebox or a individual drives, you
should keep in mind the fact that optical disks are not as of yet an
especially fast medium.

In our system the optical disks are accessed through a server.  The
server is responsible for satisfying read and write requests in the
most efficient possible manner.  The server has a hard disk for staging
data to be written to optical disk and caching data read from optical
disk.

Writing data to the server is, in general, faster than writing to
optical disk, as the server will first write the data to magnetic disk
(which is faster).  Once the data is written to the server's hard disk,
the client can go about it's business.  The server will actually write
the data to optical disk at some later point in time.

There is a place for individual optical disk drives.  If you are
continuously writing large volumes of data to optical disk, it may be
more effective to have a disk attached to the machine generating the
data.  The central jukebox is a win when a large number of people wish
to share the same data.

--
Preston L. Bannister
USENET	   :	ucbvax!trwrb!felix!preston
BIX	   :	plb
CompuServe :	71350,3505
GEnie      :	p.bannister