john@geac.UUCP (John Henshaw) (03/03/88)
In article <7520@apple.Apple.Com> bcase@apple.UUCP (Brian Case) writes: >One thing is for sure though, code size is almost always much less important >that data size. I find this statement interesting. The both code and data require memory accesses so that we can perform useful work. It seems to me that we do many more accesses to fetch instructions than we do to fetch data. This is of course, offset by the fact that the code is held in very fast cache memory (if we do things right :-)). I would appreciate it if Brian, (or anyone else of course) would care to expand on the above. -john- -- John Henshaw, (mnetor, yunexus, utgpu !geac!john) Geac Computers Ltd. If we don't pay for education now, are we Markham, Ontario, Canada, eh? going to be able to pay for ignorance later?
bcase@Apple.COM (Brian Case) (03/05/88)
In article <2377@geac.UUCP> john@geac.UUCP (John Henshaw) writes: >In article <7520@apple.Apple.Com> bcase@apple.UUCP (Brian Case) writes: >>One thing is for sure though, code size is almost always much less important >>that data size. > >The both code and data require memory accesses so that we can perform >useful work. It seems to me that we do many more accesses to fetch >instructions than we do to fetch data. This is of course, offset by the >fact that the code is held in very fast cache memory (if we do things >right :-)). > >I would appreciate it if Brian, (or anyone else of course) would care >to expand on the above. Er, I think I should have been more explicit. I meant to say that "The number of bytes of data is much greater than the number of bytes of code in most applications." There may be, understandably, some dissagreement here. I was not trying to make any points about caches or bus bandwidth or whatever. I was just saying that code can expand by a factor of two, but the problem will still be one of data size. I should say that I have this opinion because I have written compilers, eg., that build very big data structures to facilitate optimization. Code size just didn't matter. I suspect spreadsheets and word processors and editors are similar. I would be happy to verbosely answer your question, but I don't understand it.