Hangs ...

[Nicolas Sebrecht]

On Mon, Mar 28, 2011 at 10:26:43AM -0400, Sebastian Spaeth wrote:
> On Mon, 28 Mar 2011 15:38:36 +0200, Christoph Höger <christoph.hoeger at tu-berlin.de> wrote:
> > instabilities when two instances of offlineimap sync the same account on 
> > two different machines. I usually run offlineimap (6.2.0) every 5 
> > minutes or so. If two of my machines are active at the same time, on one 
> > offlineimap will hang with high probability.

Haha! Very interesting!

I never thought about this case before but it looks like a very
interesting case we should study to improve OfflineIMAP stability. I
guess IMAP servers handle concurrent access just fine so it would be a
good starting use case.

I'll see what I can do to provide a local IMAP server (understand for
the loopback network interface) in a chrooted environment to play with
such scenario. Also, it would be a good point for further unit tests.
Don't expect patches soon, though.

> You mean 2 instances both accessing a remote IMAP at the same time? This
> *should* work. I am not sure how well protected offlineimap when eg a
> Message on the IMAP server disappears just before it wants to modify or
> copy it. But if offlineimap can't cope with this situation, than I'd
> consider that a bug.

Yes, it would be a bug for sure: we can't freeze server data for the
time we work on.

> Please dig into the current master and not into the 6.2.0 code in case
> you dig deeper. We've had a bit of changes since then.

I'd say a frequently updated "next" checkout, instead.

-- 
Nicolas Sebrecht