Paging is still very much in use, though segmentation is used much less than in the old days.
The Opteron/EM64T architecture is essentially the same as the ia32 (pentium) architecture. Yes, the registers are now 64 bit. The big difference between ia32 and x86_64 is to the kernel, and large user space applications. The kernel no longer has to fool around with 3 zones of memory (DMA/Normal/High), and the entire address space is directly addresses by the kernel. Big database engines (and other large memory map program) no longer have to worry about virtual address space limitation. For normal users, you are probably better off on a 32 bit box. Once you move to 64 bit, you'll find lots of little gotchas... for example, Sun is yet to introduce a 64 Java plugin (last time I checked) I'd rather have twice as many processors than twice as many bits... for similar costs - jim (dual proc 3.8GHz 64bit, 8GB Ram, 1.2Terabyte of disk.... Desktop, but then, I didn't have to pay for it) On Thu, 25 Aug 2005 15:46:46 -0700 Ben Johnson <[EMAIL PROTECTED]> wrote: > On Thu, Aug 25, 2005 at 06:06:09PM +0200, Damon Jacobsen wrote: > > I had thought that 64 bit processing was more than simply more > > addressable RAM. Am I wrong? > > > > unless I'm crazy this would have to mean, at a minimum, 64 bit registers > as well. just this much means there are probably huge changes in the > cpu architecture... such as possibly flat memory addressing instead of > paging ... and stuff like that. stuff like... getting rid of memory > segmentation, which I learned is universally thought to be a huge pain > in the ass. (perhaps you can you can tell I don't know very well what > I'm talking about. But that's what I've said and I'm sticking by it! ;) > > - Ben > > > _______________________________________________ > RLUG mailing list > [email protected] > http://lists.rlug.org/mailman/listinfo/rlug _______________________________________________ RLUG mailing list [email protected] http://lists.rlug.org/mailman/listinfo/rlug
