Re: AMD K6-2 / Bogomips problem

[pat@patoche.org]

On 17-Jan-99, Phillip Deackes took time to write :
>> so my AMD K6-2 at 350Mhz should have 700Bogomips isn't it ?
>
> I think I would be concerned too. I have an AMD K6-2 3D 350 MHz

I am !

> processor, overclocked to 400MHz and I get the following from cat
> /proc/cpuinfo:
> 
> processor       : 0
> cpu             : 586
> model           : AMD-K6(tm) 3D processor
> vendor_id       : AuthenticAMD
> stepping        : A
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid           : yes
> wp              : yes
> flags           : fpu vme de pse tsc msr mce cx8 syscr mmx 3dnow
> bogomips        : 801.18

i have :
processor       : 0
cpu             : 586
model           : AMD-K6(tm) 3D processor
vendor_id       : AuthenticAMD
stepping        : M   <---- difference !!! what is it ?
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid           : yes
wp              : yes
flags           : fpu vme de pse tsc msr mce cx8 syscr pge mmx 3dnow
                                                       ^^^ difference !
what's that ?
bogomips        : 350.62

i will try to read the kernel sources if i understand anything...
but i someone knows about these things...

 
> Sorry if I state the obvious, but you are running at 3.5 x 100 MHz? You
                                                       ^^^^^^^^^^^^^
i have to check tomorrow directly on the main board (is that what you think :
multiplier and bus frequency)

> do have 100 MHz memory?

i have two 64Mo chips 100MHz coming from different manufacturers (could that
be the cause ?)
will bogomips change if memory changes ?
 
> I have found in the past on a couple of occasions I have had ludicrously
> low bogomips figures and have re-compiled the kernel (not even changing
> the settings!) and the rate has gone up the next time i have re-booted.
> Only ever happened with a RedHat system - don't know why.

isn't that strange ?
bogomips should only depend on hardware no ?

> What kernel are you using? There are a couple of AMD K6-2 patches
> around.

2.0.36 without any patch i can think of.

otherwise the 'compile as [386/486/Pentium/PentiumPro]' option in kernel
compilation could change the bogomips rating or not ?
i compiled it as a 686.
should i compile it as a 586 ?

Patrick