Joe Landman wrote:
We know of (and have worked with) many applications that have required tremendous memory footprint. One that required hundreds of GB of ram in the late 90s might use a bit more today.
I claim that there's a memory-related constant that hasn't been widely recognized. This is that the amount of address space for a program's text segment will never exceed 32 bits. Note that I am *not* talking about the data segment. The reason for this is that it's simply too hard to write a program whose instructions require even close to the 32 bit address space. Such a program would be too complex to understand, assuming it's written by humans. Maybe such a program could be generated by a program, but I'm not talking about this. I once added up the text segment of every executable and shared library on a Linux system. I probably counted some files more than once. Even so, the total text size of all these files was less than 2GB. I'm not proposing doing anything about this, such as coming out with an architecture that uses 32-bit text pointers and 64-bit data pointers. That would add needless complexity. But, it's important to realize that this limit exists, and unless we get much smarter, isn't likely to go away. Cordially, -- Jon Forrest Research Computing Support College of Chemistry 173 Tan Hall University of California Berkeley Berkeley, CA 94720-1460 510-643-1032 jlforr...@berkeley.edu _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
