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Behind the 4GB Memory Limit In 32-Bit Windows
An anonymous reader points us to a very detailed post by Geoff Chappell, first put up early this year, explaining how the 4GB memory limit commonly bandied about for 32-bit Windows (he is writing mainly about Vista) is more of a licensing preference than an architectural limit. The article outlines how Chappell unlocked his system to use all the memory that is present, but cautions that such hackery is ill-advised for several reasons, including legal ones. "If you want [to be able to use more than 4GB in Vista] without contrivance, then pester Microsoft for an upgrade of the license data or at least for a credible, detailed reasoning of its policy for licensing your use of your computer's memory. ... [C]onsider Windows Server 2008. For the loader and kernel in Windows Vista SP1 (and, by the way, for the overwhelming majority of all executables), the corresponding executable in Windows Server 2008 is exactly the same, byte for byte. Yet Microsoft sells 32-bit Windows Server 2008 for use with as much as 64GB of memory. Does Microsoft really mean to say that when it re-badges these same executables as Windows Vista SP1, they suddenly acquire an architectural limit of 4GB? Or is it that a driver for Windows Server 2008 is safe for using with memory above 4GB as long as you don't let it interact with the identical executables from Windows Vista SP1?"
As long as we maintain the ability to run 32-bit programs on those 64-bit operating systems. I have Perl programs that parse and analyze very large log files. Their memory usage went up by a factor of about 1.5 when I switched to a 64-bit system. This was not good, since they were running at about 90% of RAM on the 32-bit system. On the 64-bit system, they swapped heavily, and my nice 10 minute report became a not so nice all day report.
I now pick the 32-bit version of Linux distributions, even on 64-bit capable hardware, unless I actually need 64-bit.
Just like that airplane seat, hotel room, rental car, theater ticket, etc... the same thing is sold for different prices according to willingness to pay. Just like senior discounts.
It's econ 101. demand curve pricing. if the demand versus price curve is actually curved with a long tale then maximum profit is achieved when a company is able to segregate consumers by willingness to pay. Your revenue is the are under the curve. and single price just gets the area of the larges rectangle you can place under the curve.
Econ 201: in second term economics we learn that the price demand curve is not actually a single curve but is a family of curves parameterized by the total number of units manufactured. So as the company is able to sell things at different prices to more people the entire curve shifts down, making it either cheaper for everyone, or mor profitable for the company depending who gets the benefit of the increased production.
even though it's galling to know the product you bought is just a dumbed down version of a beter one at no difference in manufacturing costs it may well be much cheaper than it would have been had they sold one thing at one price.
Of course it may be that your customers hate this. a few companies like Apple and Saturn use a more price fix model precisely because it fits their style of minimizing aggravation. But even they have college student or military discounts.
Some drink at the fountain of knowledge. Others just gargle.