64-bit program memory usage

Ning Jin ning@vitesse.com
Wed Jun 18 00:28:00 GMT 2003


I recently re-compiled my old C code to 64-bit on Solaris 8
using gcc 3.2.0 with -m64 switch. It turns out that the 64-bit version uses
twice as much memory as the 32-bit counterpart does. My program reads
large data files into memory so memory usage is big concern. With one 
of my testcases, the 32-bit uses 2.1G while the 64-bit uses 4G memory.

I do use pointers intensively as I need to store them in binary
tree type of structure. Is that the reason why memory usage gets doubled
(since pointers are all 64bit now)? Any cure?

Thanks,

NJ



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