Re: [PATCH v4 net-next 2/3] net/udp: Add 4-tuple hash list basis

[Paolo Abeni <pabeni@redhat.com>]

On 10/16/24 08:30, Philo Lu wrote:
> On 2024/10/14 18:07, Paolo Abeni wrote:
>> It would be great if you could please share some benchmark showing the
>> raw max receive PPS performances for unconnected sockets, with and
>> without this series applied, to ensure this does not cause any real
>> regression for such workloads.
>>
> 
> Tested using sockperf tp with default msgsize (14B), 3 times for w/ and
> w/o the patch set, and results show no obvious difference:
> 
> [msg/sec]  test1    test2    test3    mean
> w/o patch  514,664  519,040  527,115  520.3k
> w/  patch  516,863  526,337  527,195  523.5k (+0.6%)
> 
> Thank you for review, Paolo.

Are the value in packet per seconds, or bytes per seconds? Are you doing 
a loopback test or over the wire? The most important question is: is the 
receiver side keeping (at least) 1 CPU fully busy? Otherwise the test is 
not very relevant.

It looks like you have some setup issue, or you are using a relatively 
low end H/W: the expected packet rate for reasonable server H/W is well 
above 1M (possibly much more than that, but I can't put my hands on 
recent H/W, so I can't provide a more accurate figure).

A single socket, user-space, UDP sender is usually unable to reach such 
tput without USO, and even with USO you likely need to do an 
over-the-wire test to really be able to keep the receiver fully busy. 
AFAICS sockperf does not support USO for the sender.

You could use the udpgso_bench_tx/udpgso_bench_rx pair from the net 
selftests directory instead.

Or you could use pktgen as traffic generator.

Thanks,

Paolo