Re: Netperf UDP_STREAM regression due to not sending IPIs inttwu_queue()

From: Eric Dumazet
Date: Wed Oct 03 2012 - 06:37:15 EST


On Wed, 2012-10-03 at 10:47 +0100, Mel Gorman wrote:
> On Tue, Oct 02, 2012 at 03:48:57PM -0700, Rick Jones wrote:

> > PS - I trust it is the receive-side throughput being reported/used
> > with UDP_STREAM :)
>
> Good question. Now that I examine the scripts, it is in fact the sending
> side that is being reported which is flawed. Granted I'm not expecting any
> UDP loss on loopback and looking through a range of results, the
> difference is marginal. It's still wrong to report just the sending side
> for UDP_STREAM and I'll correct the scripts for it in the future.

You can have drops even on loopback if the receiver doesnt drain its
socket receive queue fast enough.



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