[PATCH] Using TCP_NODELAY unconditionally

Nicolas Williams Nicolas.Williams at ubsw.com
Wed Jan 23 05:22:34 EST 2002


On Tue, Jan 22, 2002 at 10:17:29AM -0800, Rick Jones wrote:
> I think that if ssh is operating as a pipe (is that the same as port
> forwarding), then if it sets TCP_NODELAY, so long as it does not do
> something silly like gratuitously sending logically associated data in
> separate sends, it will preserve the behaviour of the apps on either
> side - whether they set TCP_NODELAY or not.
> Data will arrive at the sockets the way it came-out of the TCPs on
> either end.

Yes, agreed. Unfortunately these SSH pipes sometimes come associated
with an interactive character based session, where Nagle is
appropriate.

> > If heuristics will do, great. It sounds like it should be simple to fix
> > sftp to avoid Nagle. Any other ideas that might fix X11 forwarding? Does
> > anyone find it necessary?
> Since X11 sets TCP_NODELAY,one could either treat it as an example of
> a generic pipe (ie set TCP_NODELAY), or one could treat it as specific
> knowledge of the needs of the application - and in this case again set
> TCP_NODELAY.

A heuristic approach may be the best. Certainly it would be the easiest.

> rick jones


Cheers,

Nico
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