Subject: Re: [PATCH net-next v2] net: Add sysctl to toggle early demux for tcp and udp

From: Subash Abhinov Kasiviswanathan <[email-masked]>
Date: Thu, 09 Mar 2017 22:26:10 -0700

On 2017-03-09 20:42, Tom Herbert wrote:
> On Thu, Mar 9, 2017 at 7:31 PM, Subash Abhinov Kasiviswanathan
> <[email-masked]> wrote:
>> Certain system process significant unconnected UDP workload.
>> It would be preferrable to disable UDP early demux for those systems
>> and enable it for TCP only.
>> 
> Presumably you want this for performance reasons. Can you provide some
> before and after numbers?

Hi Tom

We are working on UDPv6 performance issues seen on an Android ARM64 
system.
Adding an early demux handler (link below) for it helped to increase 
performance
(800Mbps -> 870Mbps). This helps because Android statistics rules do 
multiple
socket lookup when no socket is associated with the skb.

https://www.mail-archive.com/[email-masked]/msg157003.html

Eric mentioned that server loads usually see more unconnected load and 
he
preferred to turn off early demux for UDP, hence this patch. I don't 
have numbers
for unconnected loads as of now though.