Randall R Schulz wrote:
On Friday January 23 2009, David Bolt wrote:
On Thu, 22 Jan 2009, Randall R Schulz wrote:-
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What it does mean, of course, is that for any given hardware and mix of applications, swapping will be _more_ likely, since all 64-bit code and data are substantially larger than their 32-bit counterparts.
The code itself may be bigger but, looking at the sizes of applications in /bin on both a 32bit and 64bit system, and the libraries in /lib abd /lib64, I wouldn't say the sizes are anything more than about 10% bigger.
Use the "size" command, not the file size.
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As for the data, why would it be "substantially" larger on a 64bit system? Pointers are going to be bigger on the 64bit system, as are variables of type "long", since these are 64bit, but those of type "int", and smaller, still occupy the same sizes in both the 32bit and 64bit OSes.
It's "substantial" because every pointer and every int is twice as big in a 64-bit programming model compared to a 32-bit one.
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Regards, David Bolt
Randall Schulz
A 64 bit processor simply has bigger internal registers and is therefore able to handle for instance a 64 bit calculation with one instruction instead of at least 3 for a 32 bit processor. The instruction is capable of being 64 bits in size but I doubt if the instruction set has increased in size to the point where that is necesary. The program counter register's size is determined by the size of the address space and not the size of the data bus. For instance the 64 bit celeron I'm running has address sizes : 36 bits physical, 48 bits virtual in cpuinfo and that would indicate a 36 bit program counter, been out of this for too long, which is expandable to 48 bits. The extent that a 64 bit processor out performs a 32 bit one is dependent on the optimization in the compiler used to compile the program. All this said I haven't ever done assembly programming for anything bigger than a 586. Regards Dave P -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org