Subject: Re: TCP_NODELAY and full links (was Re: sup problems?)
To: None <current-users@netbsd.org>
From: Feico Dillema <dillema@acm.org>
List: current-users
Date: 09/29/1999 03:03:33
On Tue, Sep 28, 1999 at 05:39:00PM -0700, Jonathan Stone wrote:
> 
> In message <199909290028.RAA27609@lestat.nas.nasa.gov>,
> Jason Thorpe writes:
> 
> It's a classic example of "be liberal in what you accept, conservative
> in what you send".  Freebsd does the same thing, for much the same
> reasons (or did, a couple of years ago) and when netbsd-current turned
> on path-MTU discovery by default, that caused problems for a few users.

I think (but am certainly not sure) that FreeBSD has PMTU discovery on
by default now. That's how I discovered it was off by default in
NetBSD. I wondered what was the cause of the performance difference
between FreeBSD and NetBSD on a 100Mbs Etherlink. Switching on 
PMTU disc. seemed to make up for most of it.

Am I right to conclude that it is safe or at least reasonable to have
PMTU disc. switched on for a server not directly behind such a
blackhole? How about clients behind such a blackhole? Will they be
blocked?

Feico.