Subject: Re: Q: netdev: generate kobject uevent on network events.

From: Benjamin LaHaise <[email-masked]>
Date: Wed, 9 Dec 2009 13:54:09 -0500

On Wed, Dec 09, 2009 at 07:46:26PM +0100, Kay Sievers wrote:
> Can't, in some setups, these events happen at a rather high frequency?
> I heard of people running many hundreds of ppp interfaces on a single
> box acting as a DSL concentrator.

/me waves

Yes, DSL concentration is looking at tens of thousands to a hundred thousand 
interfaces on current hardware with 10G links.

> They state to already have trouble
> handling the amount of uevents generated on such boxes just for the
> "add/remove" events of all the interfaces if something goes wrong with
> the network. If we add more for state transitions, such events would
> probably need to be rate-limited. In general, uevents/udev are not
> really suitable for high-frequency events, and if such behavior can be
> expected, we might better stick with the current netlink interface.

Duplicating events in different delivery mechanisms seems pointless.  A 
simple netlink listener can be done in less than a hundred lines, so I don't 
see the need for the duplication.

		-ben