Re: [PATCH net-next 1/4] netlink: truncate overlength attribute list in nla_nest_end()

On Wed, 7 Jun 2023 09:52:54 -0700 Stephen Hemminger wrote:

quoted

Hm, you're right. But allocation larger than 32kB are costly.
We can't make every link dump allocate 64kB, it will cause
regressions on systems under memory pressure (== real world).

You'd need to come up with some careful scheme of using larger
buffers.  

Why does it all have to be a single message?
Things like 3 million routes are dumped fine, as multiple messages.

The old API we can't change. The new API is switchdev / devlink,
and it's already in place. We'd have to add a third API, like 
the old one but with different msg format which for obvious 
reasons I'd prefer not to do.