Hi Tim,
Tim Peters wrote at 2006-3-31 18:48 -0500:
...
What is the motivation to request synchronized transaction completion
by default?
Primarily so we could stop seeing endless threads on zodb-dev asking
why ZEO clients that didn't happen to modify any objects never saw
current data. From the NEWS file:
- (3.4a6) Relatedly, ``Connection`` implements ``ISynchronizer``, and
``Connection``'s ``afterCompletion()`` and ``newTransaction()`` methods now
call ``sync()`` on the underlying storage (if the underlying storage has
such a method), in addition to processing invalidations. The practical
implication is that storage synchronization will be done automatically now,
whenever a transaction is explicitly started, and after top-level
transaction commit or abort. As a result, ``Connection.sync()`` should
virtually never be needed anymore, and will eventually be deprecated.
Based on my observation, I fear it is a too expensive measure.
If an asyncore mainloop (or something equivalent) is running,
then we would get the same effect without the sync.
Maybe we should go this route (and ensure instead that a mainloop is
always running).
--
Dieter
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