[darcs-users] Re: peer to peer darcs

[S. Alexander Jacobson]

On Sun, 1 Aug 2004, Eric S. Johansson wrote:
> > Anyhow, on today's internet, you probably don't have to worry about
> > people getting so far out of sync that this is really an issue.  Or am I
> > wrong?

The maximum out-of-syncness is the duration of the
period between batch retrievals/sends of email.

If your workgroup includes people who are actively
producing patches with long periods between such
connections, then you probably have to handle that
specially no matter what revision control system
you are using.

However, I think, in most workgroups, a 2-3 day
period assumption seems entirely reasonable and
workable...

> I think you are overly optimistic.  Today's Internet is mostly broken
> into consume only notes and a few producers.  For peer-to-peer
> operations, you need end-to-end completeness and that just isn't happening.

You have end-to-end completeness for asynchronous
communications via email and arguably instant
messaging (e.g. Jabber).

> again personally, sending changes by SMTP doesn't really fit with my
> development style so I can't evaluate whether or not its useful.
> Apparently it works for some and I'm glad it does.

I agree that in some cases you can do better than
SMTP.  Perhaps the distribution list should be a
list of URLs rather than simply email addresses
where the URL schemas implicitly specify how
patches are delivered over that protocol.  e.g.
"mailto:" implies the gpg wrapping mechanism
described in the docs, "http:" implies POST the
gpg package, etc.  Each line in the distribution
list mightt optionally include a public-key for
the recipient (resulting in end-to-end
encryption).

But before we do all this, I'd like to understand
whether the base p2p model is actually plausible.
The minimal-context discussion has been going a
bit over my head...

David, Eric, if we make the assumption that people
will get maximally n days out of phase or that
there will be at most e.g. 1000 patches in the
time that people are out of phase, how bad is
O(n^2) when n==1000 on modern computers?

> from the consumer side, maybe it's just my style but I can't see getting
> automatic updates except as e-mail notices saying that something changed
> with enough information so I could decide whether or not to pull the
> changes.

Ok.  I think both POP and IMAP allow you to
retreive headers without retreiving message
bodies. Alternatively, if you receive patches via
HTTP, how you get notified about the content of
those changes would be a local configuration
issue...

-Alex-

______________________________________________________________
S. Alexander Jacobson tel:917-770-6565 http://alexjacobson.com