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From: sasaki@HARVARD.HARVARD.EDU.UUCP
Newsgroups: mod.computers.vax
Subject: RAM disks on VAX
Message-ID: <8702161641.AA16176@ucbvax.Berkeley.EDU>
Date: Mon, 16-Feb-87 11:39:43 EST
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Posted: Mon Feb 16 11:39:43 1987
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One warning, the PDDRIVER is fairly slow. The transfer from the "disk"
to the user's buffer is done a byte at a time, rather than a movc3.
Remember too that this slow transfer is done a at elevated IPL.

We were thinking of setting aside a few megabytes on our 8650's to put
commonly used images and small databases. Rather than improve
performance, overall performace actually went down. This might be due
to the particular work load.
----------------
  Marty Sasaki				uucp:   harvard!sasaki
  Ziff Davis Technical Information Co.	arpa:	sasaki@harvard.harvard.edu
  80 Blanchard Road			bitnet: sasaki@harvunxh
  Burlington, MA 01803			phone:	617-273-5500