Hey Mulyadi,

On Thu, Oct 21, 2010 at 9:59 PM, Mulyadi Santosa
<[email protected]> wrote:
> Hi..

>
> IMHO it is the  "in cache" speed which is folded unlinearly. Due to
> L1/L2/L3 nature, it might be that the whole code is already in the
> same cache line thus subsequent call doesn't fetch anything from RAM.
> This is assuming everything is (almost) perfectly cache aligned.
>
> BTW, are all the codes executed? or are we hitting 10/90 percent scenario 
> here?
>

In my module I am doing a "wbinvd" which invalidates the cache. So it
must definitely
try to fetch from RAM as there will be a cache miss.

I am _mostly_ sure that I am messing up MTRR. Not enough documentation
out there for it.
I just tried disabling only MTRR(without using the above module) and
the slowdown is still there.

Even after re-enabling MTRR range, the slowdown persists.(check my
other mail for details).

Regards,
Andev

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