Subject: Re: [PATCH 08/24] net, diet: Make TCP metrics optional

From: [email-masked]
Date: Tue, 6 May 2014 10:30:15 -0700

On Tue, May 06, 2014 at 10:03:24AM -0700, Eric Dumazet wrote:
> On Tue, 2014-05-06 at 09:45 -0700, [email-masked] wrote:
> 
> > Sounds like we have some optimization to do, then; there's no
> > fundamental unfixable reason for that delta.
> 
> I think you have little idea of the reasons for this delta.

I have a rather good idea, actually.

> Some servers handle 10 millions of TCP flows, using as little as 1KB per
> connection in user space, all included.
> 
> Do you have an idea of how much memory is needed for 10 millions TCP
> sockets in the kernel ?

Too much.  That's potentially fixable, but not if we start with the
premise that it's impossible.

- Josh Triplett