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Re: databases bombing

On Fri, 9 Jan 2009, Geert Hendrickx wrote:

On Fri, Jan 09, 2009 at 12:55:23PM +0000, David Brownlee wrote:
Thanks for catching this - Intel appear to have re-used cpu branding
strings between Northwood and Prescott pentium4s.  Which is just...
special and annoying.

cpuflags now handles this by explicitly testing for SSE3 support to
distinguish between '-march=prescott' and '-march=pentium4' fixed in
v1.32 and apologies for the pain...

There seem to be similar cases like this:

cpu_name="Intel Pentium III (Katmai) (686-class), 2660.15 MHz, id 0x10677"
cpu_brand="Intel(R) Core(TM)2 Quad  CPU   Q9450  @ 2.66GHz"

Here cpuflags suggests "-mfpmath=sse -msse3 -march=prescott", while I use
"-march=nocona" (gcc 4.1).

        I have the fallback for 'core2' as 'pentium-m' which I think
        may be better for instruction scheduling, but omits the
        SSE3 support of 'nocona'. On balance I think 'nocona' is
        probably a better choice.

        Could you test cpuflags 1.34 (the issue with it not picking
        it up as core2 to start with should be resolved)

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