Re: [PATCH net-next 0/4] net: route: improve route hinting

[Leone Fernando]

David Ahern wrote:
> I have looked at all of the sets sent. I can not convince myself this is
> a good idea, but at the same time I do not have constructive feedback on
> why it is not acceptable. The gains are modest at best.
> 

Thanks for the comment.

I believe an improvement of 5-8% in PPS is significant. 
Note that the cache is per-cpu (e.g., for a machine with 10 CPUs, the improvement
affects 10X the conns mentioned).

Could you please provide more information about what you don't like
in the patch?

Some possible issues I can think of:
- Do you think the improvement is not affecting the common case?
In this case, it can be solved by tweaking the cache parameters.

- In case performance degradation for some # of conns is problematic - we can
find ways to reduce it. For example, the degradation for 1 connection can
probably be solved by keeping the route hints.

Leone