I think what he meant was ' no application needs more than 640k - the rest is for the operating system'
On Fri, 16 Jun 2023, 08:43 Steve Lewis via cctalk, <cctalk@classiccmp.org> wrote: > I don't think Gates ever actually said this - but that's just based on my > own examination into this from a few years back. > > But, over the years I've done some thread programming, and I was once > solving a problem by loading a lot of data into main memory (like 8-16GB of > data to process as one huge chunk, on a system that only had 32GB total). > > A while later, I had a thought that actually maybe this quote has some > merit. Maybe not the specific amount (of 640KB) - but the general notion > that there is rarely a reason for a single application to consume the > entirety of main memory. It may be better, especially with threads or > multi-core, to work a problem in smaller chunks -- specifically, to work a > problem in chunks smaller than the CPU cache. And in fact, I found a huge > jump in my programs performance when I kept the buffers exactly 1 byte less > than the CPU cache (at the time that was 1MB) - as soon as I went 1 byte > over, I noticed a huge (~3X) hit in performance. Now that's just a single > data point, and the old advise of "never optimize your program for > performance too early" is probably still good. And especially most shops > won't spend the time/resources to cache optimize their builds - I suspect > some games do at startup, they maybe profile what your L3 cache size. > > > Anyhow, years ago I recall coming across a quote or an article where Gates > stated the IBM PC (or maybe the 8088 cpu itself) was designed or intended > to only "last" about 10 years. Not that the system components itself would > only last that long, but as it being a "useful" system. In that context, > maybe he was right (if he had said it) - 640K was maybe "enough for anyone" > for the remainder of the 1980s. I recall starting with 384KB (thinking > anything past 128KB was "huge") and doing upgrades in the late 1980s to get > to 640KB, and not getting into extended/expanded memory until the early > 90s. This would be for "typical" household applications (taxes, small > business, word processing) - obviously image processing (CAD, movie > rendering, etc.) or multi-user servers do need more memory. > > I also recall that it was Intel that requested to keep it to 10 segments of > 64KB (640KB), not really a Microsoft or MS-DOS doing. i.e. aspects beyond > Microsoft wanted to reserve the "upper memory" for other stuff (video > memory). You have 16 segments, how many to hold in reserve? Someone > chose 6. Quick and Dirty OS indeed. > > > > On Tue, Jun 13, 2023 at 11:47 PM Ali via cctalk <cctalk@classiccmp.org> > wrote: > > > So I had always heard the quote "640KB is enough memory" being attributed > > to > > Bill Gates. However, recently I was watching Dave Plummer on YT and he > said > > that it is not true: > > > > https://youtu.be/bikbJPI-7Kg?t=372 > > > > And apparently the man himself has denied it as well but it just will not > > go > > away... > > > > https://abcnews.go.com/Technology/PCWorld/story?id=5214635 > > > > So I guess like the napkin/disk story and the DR/IBM story this is > another > > one of those vintage myths and folk lore with no real basis in > reality.... > > > > -Ali > > > > > > > > >
