Block replication slot advance for these not yet reserving WAL
Such replication slots are physical slots freshly created without WAL
being reserved, which is the default behavior, which have not been used
yet as WAL consumption resources to retain WAL. This prevents advancing
a slot to a position older than any WAL available, which could falsify
calculations for WAL segment recycling.
This also cleans up a bit the code, as ReplicationSlotRelease() would be
called on ERROR, and improves error messages.
Reported-by: Kyotaro Horiguchi
Author: Michael Paquier
Reviewed-by: Andres Freund, Álvaro Herrera, Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180626071305.GH31353@paquier.xyz
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/56a714721343e6f52c0b1b911c0f160592348e84
Modified Files
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contrib/test_decoding/expected/slot.out | 17 +++++++++++++++++
contrib/test_decoding/sql/slot.sql | 6 ++++++
doc/src/sgml/catalogs.sgml | 3 ++-
src/backend/replication/slotfuncs.c | 13 ++++++++-----
4 files changed, 33 insertions(+), 6 deletions(-)