I'm not sure about some of the details.
I think it would make more sense to reset ApplyMessageContext in
apply_dispatch(), so that it is done consistently after every message
(as the name implies), not only some messages.
Also, perhaps ApplyMessageContext should be a child of
TopTransactionContext. (You have it as a child of ApplyContext, which
is under TopMemoryContext.)
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Peter Eisentraut http://www.2ndQuadrant.com/
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