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From: kenw@noah.arc.CDN (Ken Wallewein)
Newsgroups: comp.os.vms
Subject: RAM DISK FOR VMS
Message-ID: <661*kenw@noah.arc.cdn>
Date: Thu, 23-Jul-87 02:21:40 EDT
Article-I.D.: noah.661*kenw
Posted: Thu Jul 23 02:21:40 1987
Date-Received: Sat, 25-Jul-87 04:31:53 EDT
References: <8707191149.AA16595@ubc.csnet>
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  The August/86 and June/87 issues of the VAX Professional contain articles on
the PDA device. Summary: it's slower than an RA81. Reason: it doesn't use DMA,
and it MOVB rather that MOVCx to move data, to avoid page faults in IPLFORK.
Incidentally, I don't understand why there couldn't be some way to predict when
page faulting would occur, so repeated MOVCx instructions could be used.

  Looks like you'd be better off optimizing your caching. BTW, from what I can 
see (I'm no expert), INSTALL works for data files, too.

/kenw