Xref: utzoo comp.arch:17587 comp.databases:6736 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!mintaka!bloom-beacon!world!ksr!clj@ksr.com From: clj@ksr.com (Chris Jones) Newsgroups: comp.arch,comp.databases Subject: Re: Extremely Fast Filesystems Keywords: addressing,fractions,floating-point,caches Message-ID: <757@ksr.com> Date: 8 Aug 90 03:12:27 GMT References: <5539@darkstar.ucsc.edu> <13285@yunexus.YorkU.CA> <30728@super.ORG> <13667@cbmvax.commodore.com> <13578@yunexus.YorkU.CA> Sender: news@ksr.com Reply-To: clj@ksr.com (Chris Jones) Followup-To: comp.arch Organization: Kendall Square Research Corp Lines: 23 In-reply-to: rbw00@ccc.amdahl.com ( 213 Richard Wilmot) In article , rbw00@ccc ( 213 Richard Wilmot) writes: >We always seem to exceed any addressing limit we can imagine. This is very true, at least so far. >I still think it is time to stop trying to use integers for addressing. >They always break down and probably always will. Many computers today have >floating point units. I would like to see floating point used for addressing. >It would help a great deal if addresses were not dense. What I have in mind >is for data objects to have addresses but these would be floating point and >between any two objects we could *always* fit another new object. In this way >I could expand a file from a hundred bytes to a hundred gigabytes without >changing the addresses of any stored objects. Um, I think that between any two *real* numbers you can always find another real number. Real numbers are a mathematical concept, and what is called floating point on computers merely implements a useful approximation of them. On computers with floating point, it is most definitely not the case that you can always fit another floating point number between two other such numbers. These things take up a finite number of bits, right, and that means there's a finite limit to their ordinality. -- Chris Jones clj@ksr.com {world,uunet,harvard}!ksr!clj