From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lukas Erlacher <erlacher@in.tum.de>
Subject: Re: No SO_BUSY_POLL for UDP?
Date: Wed, 18 Mar 2015 00:51:40 +0100
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On 03/18/2015 12:20 AM, Eric Dumazet wrote:
> 
> busypoll should be available on _connected_ UDP sockets. Otherwise, we
> would have to look all RX queues of the NIC, not a single one.
> 
> Try netperf  -t UDP_RR -- -N -n
> 
>     -n                Use the connected socket for UDP locally
>     -N                Use the connected socket for UDP remotely
> 
> (Although I believe netserver->netperf is ignoring the -N option, that
> is a netperf bug)
> 
> check with ss -a|grep udp
> 

Thank you very much, I was missing that bit of info. With connected
sockets, busy polling works perfectly.

Best,
Lukas Erlacher