On Thu, 2014-04-10 at 19:38 +0100, Edward Cree wrote: > On 10/04/14 19:32, Eric Dumazet wrote: > > On Thu, 2014-04-10 at 19:04 +0100, Edward Cree wrote: > > > >> Tested by setting IFF_SINGLE_NAPI in sfc; a UDP ping-pong test showed a > >> performance benefit from sysctl net.core.busy_{read,poll}=50 in both the > >> connected and unconnected case, where previously it only saw the benefit > >> when the socket had been connected. > > Right, but how often do we have single NAPI devices on hosts wanting > > very low latencies ? > > > Well, sfc only has a single NAPI context per device, and I'm fairly sure > most sfc users want very low latencies. > Or have I misunderstood? sfc is multi queue/channel, but has a single NAPI instance ? Sounds wierd. Please explain me, how GRO can be efficient. I believe you have one napi per channel. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html