[elephant-devel] Re: Updated version of last Postmodern patch bundle

[Alex Mizrahi]

 LPP>>> Can you elaborate on that? Seems complicated...
 ??>> retry-cleanup-fn? it's actually pretty simple -- it gives application
 ??>> ability to hook it's code just before restarting transaction.
 ??>> this way application can do custom cleanup.

 LPP> But how is this related to the txn isolation level?

retry handling was not implemented because there was very little need for 
retries in absense of concurrent conflicts (pgsql does not signal those 
conflicts if you're using default read commited isolation level).
theoretically we could get a deadlock, but it only happens if application 
updates object in different order, and this can be avoided.

also, we have a race condition in update-or-insert implementation, but this 
could be avoided either via savepoints, or via locking.

so, we could live without transaction retrying unless we really need 
serializable isolation level.