On Tuesday 19 December 2006 14:48, John Andersen wrote: > On Tuesday 19 December 2006 13:31, Randall R Schulz wrote: > > John, > > > > On Tuesday 19 December 2006 14:09, John Andersen wrote: > > > On Tuesday 19 December 2006 08:11, Randall R Schulz wrote: > > > > ASUS P5B Deluxe > > > > Core 2 Duo > > > > 32-bit Linux install > > > > > > How did That happen? Core 2 is x86_64 by default... > > > > Says who? What "default?" > > Well, Randall, since your past responses suggest you > are a big wikipedia fan, check here: > > http://en.wikipedia.org/wiki/Core_2_duo
Wikipedia is a good thing, yes. > Its a 65bit processor. It will emulate 32bit. 65? The question was not about what it can do, but what it's "default" is. > You incur some penalty in installation size (disk space) > but since the bulk of an os is moving stuff around in memory > you will gain the use of 64bit registers to do this if you install > the 64bit kernel. Think more about this. The primary bottleneck in modern desktop-style computers is the memory interface. The limiting factor there derives from the cycle time of the RAM and the width of the transfer bus. Using a 64 bit processor does not change those parameters. However, it does mean that all addresses and single-word values are 64-bits wide, and transferring that any number of such 64 bit quantities is going to take twice as long as transferring the same number of 32-bit quantities. If all you're doing is a lot of string copies, you won't find much difference. But if you're doing integer arithmetic in programs written in C or C++ and those programs are compiled for the 64-bit ISA, then you're going to be moving a whole lot of high-order zero bits around. If you don't need a 64-bit architecture, you definitely should not use one. I don't need one. Randall Schulz -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
