Re: [PATCH v3] net:Add sysctl_max_skb_frags

[Alexander Duyck]

On Wed, Feb 3, 2016 at 9:54 AM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> On Wed, 2016-02-03 at 09:43 -0800, Alexander Duyck wrote:
>
>> Read the history.  I still say it is best if we don't accept a partial
>> solution.  If we are going to introduce the sysctl as a core item it
>> should function as a core item and not as something that belongs to
>> TCP only.
>
>
> But this patch is the base, adding both the core sysctl and its first
> usage.
>
> Do we really need to split it in 2 patches ? Really ?
>
> The goal is to use it in all skb providers were it might be a
> performance gain, once they are identified.

That is what I thought.  So why are we trying to sell this as a core
change then.  All I am asking for is the sysctl to be moved and
renamed since based on all of your descriptions this clearly only
impacts TCP.

> Your points were already raised and will be addressed, by either me or
> you. And maybe others.

Please don't sign me up for work I didn't volunteer for.  I already
have enough broken code to try and fix.  I'm pretty sure I need to go
in and fix the gso_max_size code for starters.

If this is only meant to be a performance modification and is only
really targeted at TCP TSO/GRO then all I ask is that we use a name
like tcp_max_gso_frags and relocate the sysctl to the TCP section.
Otherwise if we are actually going to try to scope this out on a wider
level and limit all frags which is what the name implies then the
patch set needs to make a better attempt at covering all cases where
it may apply.

- Alex