On 17 August 2017 at 07:30, Michael Paquier <michael.paqu...@gmail.com>
> Definitely agreed on that. Any move function would need to check if
> the WAL position given by caller is already newer than what's
> available in the local pg_wal (minimum of all other slots), with a
> shared lock that would need to be taken by xlog.c when recycling past
> segments. A forward function works on a single entry, which should be
> disabled at the moment of the update. It looks dangerous to me to do
> such an operation if there is a consumer of a slot currently on it.
ERROR's on logical slot, for now. Physical slots only.
Future work to allow it to use the logical decoding infrastructure to
fast-forward a slot by reading only catalog change information and
invalidations, either via a dummy output plugin that filters out all xacts,
or by lower level use of the decoding code.
Craig Ringer http://www.2ndQuadrant.com/
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