Path: utzoo!attcan!uunet!samsung!know!zaphod.mps.ohio-state.edu!brutus.cs.uiuc.edu!ux1.cso.uiuc.edu!ux1.cso.uiuc.edu!aglew From: aglew@dual.crhc.uiuc.edu (Andy Glew) Newsgroups: comp.arch Subject: Re: Extremely Fast Filesystems Message-ID: Date: 8 Aug 90 14:11:37 GMT References: <5539@darkstar.ucsc.edu> <13285@yunexus.YorkU.CA> <30728@super.ORG> <13667@cbmvax.commodore.com> <40644@mips.mips.COM> <1990Aug8.042631.7093@nlm.nih.gov> Sender: usenet@ux1.cso.uiuc.edu (News) Organization: University of Illinois, Computer Systems Group Lines: 46 In-Reply-To: usenet@nlm.nih.gov's message of 8 Aug 90 04:26:31 GMT ..> Who can use 64 bit machines? As David States points out (and several comp.arch readers who have worked on machines with large registers have testified in the past) 64 bit registers are very nice for manipulating strings in, since many strings are shorter than 8 characters. Store partial operations (with or without an implied shift) are useful. COBOL like fixed field width operations are particularly well suited to large register widths, although null terminated C-style strings can easily be handled by a number of operations that have been added to RISCs like HP's. By the way, can anyone recall the name of the PDP-11 retrospective that advocated separate address and data registers? If I remember correctly, they figured that 32 bit addresses were needed, but 16 bit integers were enough for most people's needs, so why provide things like a 32x32 multiply? (I may have misremembered, and they may have advocated 16 bit addresses but 32 bit integers, but I don't think so). I will admit that this paper influenced me for quite a while (in fact, still does, in a mixed sense); I do not know for sure, but I would also reckon that it influenced the design of two popular microprocessor families. Any bets on whether people will take the same limiting strategy (I won't call it a mistake, because it might be right for short-term goals) by providing 32 bit data registers and 64 bit address registers? -- Andy Glew, andy-glew@uiuc.edu Propaganda: UIUC runs the "ph" nameserver in conjunction with email. You can reach me at many reasonable combinations of my name and nicknames, including: andrew-forsyth-glew@uiuc.edu andy-glew@uiuc.edu sticky-glue@uiuc.edu and a few others. "ph" is a very nice thing which more USEnet sites should use. UIUC has ph wired into email and whois (-h garcon.cso.uiuc.edu). The nameserver and full documentation are available for anonymous ftp from uxc.cso.uiuc.edu, in the net/qi subdirectory.