[ZODB-Dev] Conflict resolution (was Re: Notes on using wrapper storages for record transformation)

[Vincent Pelletier]

Le lundi 24 mai 2010 17:23:54, Jim Fulton a écrit :
> Reference?

"Weak Consistency: A Generalized Theory and Optimistic Implementations for 
Distributed Transactions"
http://pmg.csail.mit.edu/pubs/adya99__weak_consis-abstract.html

> If we do conflict resolution before the commit lock is held,
> then there if a chance that the object under conflict gets updated
> again while we're doing conflict resolution, so we may have to to
> conflict resolution again. Is that the case you're talking about?

Yes.

> That's not what I said. I said it gets the lock at the end of the
> first phase.  The lock is held while conflict resolution is
> performed.

Oops, I didn't realise that ZEO was postponing Storage.store calls until 
tpc_vote call. I now realise that this is required to not interleave stores 
from different transactions in underlying storage.

-- 
Vincent Pelletier