[systemd-devel] ssh socket activation (Was: systemd unit files for Debian based systems)

[Michael Olbrich]

On Tue, Jun 19, 2012 at 07:45:47PM +0200, Lennart Poettering wrote:
> On Tue, 19.06.12 23:40, Alexander E. Patrakov (patrakov at gmail.com) wrote:
> > IMHO there is one "issue" with the inetd-style approach: it is
> > explicitly discouraged in "man sshd". It may well be the case of
> > outdated documentation, as I don't see any of the indicated problems
> > on my desktop or laptop. Still, it would be nice to clarify this
> > discrepancy in the unit file.
> 
> I think this is mostly out of date information on today's
> machines. Starting a per-connection instance is hardly distuingishable
> from single-instance sshd latency-wise, at least on my machines here.

Well, I don't have any numbers, but I think on a 200MHz ARM the situation
might be a bit different.

> (I mean, I'd be happy if somebody would make sshd single-instance socket
> activatable, but I think the inetd-style activation is pretty OK
> performance wise and Apple ships SSH like this too, so I don't see why
> we shouldn't).

I was mostly curious because of the issue in the man page. If that is no
problem any more, then inetd-style activation is ok.
ssh is mostly a debug and development tool for me anyways. And here any
socket activation is really great because there is no impact one the
startup time and memory usage but it's still available when needed.

Michael

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