[PATCH] Using TCP_NODELAY unconditionally

[Rick Jones]

> The latter.

Then port forwarding trumps.

> Do you use SSH?

Yes.

> It's like TELNET, but it can also do port forwarding
> over the same TCP connection as the main session,

But I've not used that feature. (At least not knowingly...)

> and it always encrypts TCP traffic, and it supports a variety of
> authentication mechanisms, but its main use is as a replacement for
> TELNET/RLOGIN.

Which has been my end-user experience thusfar (well, and scp).

> The main SSH abstraction that you should be interested in, wrt this
> discussion, is the channels abstraction, whereby SSHv2 multiplexes
> multiple streams onto one TCP session - some channels may be
> associated with, say, a login session, whereas others may be
> associated with X11 forwarding.

So, ssh is both the floor wax and the desert topping... 

Modulo all the vendors having been forced to kludge their telnets to
disable nagle by default (grrrr) I would say that an interactive session
should start with nalge still on (my quixotic hope of undoing the
aforementioned telnet kludges) but when ssh is acting as a session-layer
mux that the presence of a second session over the same TCP connection
calls for setting TCP_NODELAY. Otherwise, two applicatoins that know
nothing about one another, which would otherwise _not_ run afould of the
interaction between nagle and delayed ack on their own would start to
run afould of it.

I still hold-onto the quixotic hope of keeping nagle on for single
session connections.

rick jones
-- 
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these opinions are mine, all mine; HP might not want them anyway... :)
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