Re: loaded router, excessive getnstimeofday in oprofile

Nick Piggin
2008-08-28T00:45:29Z

On Thursday 28 August 2008 08:39, Andi Kleen wrote:
> On Wed, Aug 27, 2008 at 03:18:24PM -0700, David Miller wrote:
> > From: Andi Kleen <andi@firstfloor.org>
> > 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).

Would it make sense to make a new option for these socket timestamps
and encourage some apps move over to it?