Erik Hofman wrote:
> No, 64-bit is by default a bit slower. It's on very special
> occasions that 64-bit outperforms 32-bit (due to data transfer
> rate...)

That's true in the general case, because the larger pointer size
effectively reduces the size of the L1 cache.  But for this
particular architecture, there are 8 extra (i.e. twice as many)
general purpose registers available in 64 bit mode.  Most CPU
benchmarks seem to show about a 10-20% speedup when run on an
AMD64 in 64 bit mode.

But compilation (especially FlightGear's final link, which is,
heh, awfully thrashy) is very often I/O bound, especially on a
laptop with a slow disk.  I guess in this case any CPU speedup is
offset by the extra I/O to write the larger binary and the
difference ends up as noise. :)


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