From: Simon Horman <simon.hor...@netronome.com> Date: Tue, 18 Apr 2017 17:09:04 +0900
> On Wed, Mar 08, 2017 at 11:22:01AM -0800, Eric Dumazet wrote: >> On Wed, 2017-03-08 at 12:11 -0700, Subash Abhinov Kasiviswanathan wrote: >> > On 2017-03-08 11:40, Eric Dumazet wrote: >> > > Well, this 'optimization' actually hurts when UDP sockets are not >> > > connected, since this adds an extra cache line miss per incoming >> > > packet. >> > > >> > > (DNS servers for example) >> > >> > Hi Eric >> > >> > Thanks for your comments. Would it be preferable to disable early demux >> > for the >> > servers with large unconnected workloads in that case? >> >> Well, many servers handle both TCP and UDP. >> >> For TCP, there is no question about early demux, this is definitely a >> win. >> >> We probably should have one sysctl to enable TCP early demux, one for >> UDP early demux. > > If early demux is a clear win for TCP then I wonder if it is > unnecessary and by some leap also undesirable to have a configuration > knob for that case. For forwarding workloads it is pure overhead since the early demux will never find a local socket, and therefore it is wasted work.
