Re: [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to per-namespace

From: David Miller
Date: Tue Jul 24 2018 - 13:14:09 EST

From: David Ahern <dsahern@xxxxxxxxx>
Date: Tue, 24 Jul 2018 09:14:01 -0600

> I get the impression there is no longer a strong resistance against
> moving the tables to per namespace, but deciding what is the right
> approach to handle backwards compatibility. Correct? Changing the
> accounting is inevitably going to be noticeable to some use case(s), but
> with sysctl settings it is a simple runtime update once the user knows
> to make the change.
> neighbor entries round up to 512 byte allocations, so with the current
> gc_thresh defaults (128/512/1024) 512k can be consumed. Using those
> limits per namespace seems high which is why I suggested a per-namespace
> default of (16/32/64) which amounts to 32k per namespace limit by
> default. Open to other suggestions as well.

No objection from me about going to per-ns neigh tables.

About the defaults, I wonder if we can scale them to the amount of
memory given to the ns or something like that? I bet this will better
match the intended use of the ns.