Re: How to compose kernel makeoptions

[charles <charles.westerman%gmail.com@localhost>]

ha, i yearn for the time when i'm tasked to eek the last bit of process.

so man cc, cool thanks chuck.

that "info" thing still perplexes me, i don't get it.

anyway thanks for your help, right on.

charles

On Fri, Feb 25, 2011 at 8:38 PM, Chuck Swiger <cswiger%mac.com@localhost> wrote:

> On Feb 25, 2011, at 5:25 PM, charles wrote:
> > so i guess i can ignore/not worry about the makeoptions line in the
> config or/and add "-march=pentium3"
> >
> > and if that's so ... well it was strange to see the new option as a
> makeoption instead of what is was before, so i'm making something out of
> nothing perhaps.
>
> Well, you're welcome to try your own benchmarks and see for yourself
> whether there is a meaningful difference for your workload.  :-)
>
> > where do i find the march definitions? is there a master list?
>
> -march=native is easier than processing the whole list, but "man cc" (or
> "info gcc", perhaps) will give you a huge long list which starts:
>
>           i386
>               Original Intel's i386 CPU.
>
>           i486
>               Intel's i486 CPU.  (No scheduling is implemented for this
> chip.)
>
>           i586, pentium
>               Intel Pentium CPU with no MMX support.
>
>           pentium-mmx
>               Intel PentiumMMX CPU based on Pentium core with MMX
> instruction
>               set support.
>
>           pentiumpro
>               Intel PentiumPro CPU.
>
>           i686
>               Same as "generic", but when used as "march" option,
> PentiumPro
>               instruction set will be used, so the code will run on all
> i686
>               family chips.
>
>           pentium2
>               Intel Pentium2 CPU based on PentiumPro core with MMX instruc-
>               tion set support.
>
>           pentium3, pentium3m
>               Intel Pentium3 CPU based on PentiumPro core with MMX and SSE
>               instruction set support.
> [ ...and then wanders off into P4/Prescott/Nocona, AMD Athlon/Opteron, VIA
> C3, etc... ]
>
> Regards,
> --
> -Chuck