Re: loaded router, excessive getnstimeofday in oprofile

[Andi Kleen]

On Wed, Aug 27, 2008 at 03:18:24PM -0700, David Miller wrote:
> From: Andi Kleen <andi@xxxxxxxxxxxxxx>
> Date: Wed, 27 Aug 2008 18:27:35 +0200
> 
> > > Those banks really want to crank down on latency - to the point they 
> > > start disabling interrupt coalescing.  I bet they'd toss anything out 
> > > they could to shave another microsecond.
> > 
> > This change would actually likely lower their latency.
> 
> They want the timestamps, but they want it to match when the packet
> arrived at their system as closely as is reasonably possible.

Then they should use hardware time stamps which are increasingly 
available (e.g. current Intel e1000 design has them and I expect
others too). 

-Andi

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