Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!mimsy!oddjob!hao!ames!ucbcad!ucbvax!noah.arc.CDN!kenw 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> Sender: daemon@ucbvax.BERKELEY.EDU Distribution: world Organization: The ARPA Internet Lines: 11 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