Re: 64 bit F7

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Chris Jones wrote:

As they say: "Where is the killer app for 64-bit computing?"

Depends on who the "user" is, and what a "killer app" is to that user.

Most things that consumers need don't approach requiring (or seriously
benefitting from) 64 bits. But some servers and workstations can get a
lot from the wider data path and bigger address space.

Basically, code built in 64 bit mode is normally faster than the same code built in 32 bit mode. I say is normally, as it does depend on the code. Also, if you search the web for this you will find lots of interesting discussions about whether it is really the 64 bits versus 32 that make the difference, or the fact that 64 bit gcc uses SSE/SSE2 by default whereas 32 bit gcc builds do not.

Bottom line for me is I have a scientific number crunching application - Compiling and running the same code, on the same machine in 32 or 64 bit mode, I find the 64 bit build is about 40% faster (about 20% if I enable SSE/SSE2 in 32 bit mode). This is very significant and for me makes 64 bit builds well worth it.

Chris


Since requirements for computers are more intense now, building 32-bit with SSE/SSE2 by default would make sense, especially if a 20% improvement is noticed in comparison.

If the code does not make a difference now, changing the default would allow implementing code in the future that takes advantage of the features. Also both 64-bit and 32-bit builds would be closer in line.

Interesting information, though the debate ws already encountered for i386 vs. i686.

Jim

--
The less time planning, the more time programming.


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