On 2020-Jul-23, Andres Freund wrote:
> I think we should change heap_abort_speculative() to set
> HEAP_XMIN_INVALID in master.
+1
> But we can't really do anything about
> existing tuples without it - therefore we will have to forever take care
> about encountering that combination :(.
>
> Perhaps we should instead or additionally make
> HeapTupleHeaderXminInvalid() explicitly check for InvalidTransactionId?
+1 for doing it as an additional fix, with a fat comment somewhere
explaining where such tuples would come from.
Additionally, but perhaps not very usefully, maybe we could have a
mechanism to inject such tuples so that code can be hardened against the
condition.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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