Re: [tbench regression fixes]: digging out smelly deadmen.

From: Ilpo Järvinen
Date: Fri Oct 31 2008 - 07:02:28 EST


On Fri, 31 Oct 2008, Eric Dumazet wrote:

David Miller a écrit :
> From: "Ilpo Järvinen" <ilpo.jarvinen@xxxxxxxxxxx>
> Date: Fri, 31 Oct 2008 11:40:16 +0200 (EET)
> > > Let me remind that it is just a single process, so no ping-pong & other
> > lock related cache effects should play any significant role here, no? (I'm
> > no expert though :-)).
> > Not locks or ping-pongs perhaps, I guess. So it just sends and
> receives over a socket, implementing both ends of the communication
> in the same process?
> > If hash chain conflicts do happen for those 2 sockets, just traversing
> the chain 2 entries deep could show up.

tbench is very sensible to cache line ping-pongs (on SMP machines of course)

...Sorry to disappoint you but we were discussion there on my AIM9 tcp_test results :-).

--
i.