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    SubjectRe: 2.6.32-rc3: low mem - only 378MB on x86_32 with 64GB. Why?
    On Sat, 10 Oct 2009 00:28:42 +0800, Jeff Chua said:

    > From all the reading I've read about how slow 64-bit was, after doing all
    > the lean and mean compiling, 64-bit is definitely the way to go! Fast and
    > worth every bit switching to 64-bit! Now I can go for 128GB ram.

    When the MIPS, PowerPC, and Sparc architectures went from 32 to 64 bits,
    they *did* take a bit of a performance hit because it basically doubled
    the memory bandwidth usage. However, they all had a reasonably large
    number of registers in 32-bit mode. When the x86 went 64-bit, the register
    pressure relief from the additional registers usually more then outweighs
    the additional memory bandwidth (basically, if you're spending twice as
    much time on each load/store, but only doing it 40% as often, you come out
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      Last update: 2009-10-10 20:19    [W:0.019 / U:5.392 seconds]
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