Re: 2-phase commit

Andrew Sullivan wrote:
> On Sat, Sep 27, 2003 at 09:13:27AM -0300, Marc G. Fournier wrote:
> > 
> > I think it was Andrew that suggested it ... when the slave timesout, it
> > should "trigger" a READ ONLY mode on the slave, so that when/if the master
> > tries to start to talk to it, it can't ...
> > 
> > As for the master itself, it should be smart enough that if it times out,
> > it knows to actually abandom the slave and not continue to try ...
> 
> Yes, but now we're talking as though this is master-slave
> replication.  Actually, "master" and "slave" are only useful terms in
> a transaction for 2PC.  So every machine is both a master and a
> slave.
> 
> It seems that one way out is just to fall back to "read only" as soon
> as a single failure happens.  That's the least graceful but maybe
> safest approach to failure, analogous to what fsck does to your root
> filesystem at boot time.  Of course, since there's no "read only"
> mode at the moment, this is all pretty hand-wavy on my part :-/

Yes, but that affects all users, not just the transaction we were
working on. I think we have to get beyond the idea that this can be made
failure-proof, and just outline the behaviors for failure, and it has to
be configurable by the administrator.

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