Re: [PATCH nf-next] docs: networking: Update connection tracking offload sysctl parameters

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Mon, Jun 21, 2021 at 06:14:15PM +0200, Arturo Borrero Gonzalez wrote:
> On 6/17/21 8:50 AM, Oz Shlomo wrote:
> > Document the following connection offload configuration parameters:
> > - nf_flowtable_tcp_timeout
> > - nf_flowtable_tcp_pickup
> > - nf_flowtable_udp_timeout
> > - nf_flowtable_udp_pickup
> > 
> > Signed-off-by: Oz Shlomo<ozsh@nvidia.com>
> 
> Sorry for the late feedback.
> 
> In my experience the kernel docs have rather poor documents for netfilter
> sysctl parameters. I often find myself reading the source code for a deeper
> understanding of what is going on.
> 
> The docs included in this patch are too short in my opinion, example:
> 
> +nf_flowtable_tcp_pickup - INTEGER (seconds)
> +        default 120
> +
> +        TCP connection timeout after being aged from nf flow table offload.
> 
> 
> Here, having an example of the sequence of events going on with the
> conntrack entry and how this sysctl key affects it would be great. Some
> explanation of the behavior that may be observed when tuning this value
> would be nice as well.
> 
> Given the patch was merged already, you can feel free to ignore this anyway :-)

I think I can extend the flowtable documentation to include this
information:

https://www.kernel.org/doc/html/latest/networking/nf_flowtable.html

to refer to this new sysctl knobs too.

If you think something else in the big picture, please, let me know
I'll be glad to extend it.

Thanks!