Fix data-corruption hazard in WAL-logged CREATE DATABASE.
RelationCopyStorageUsingBuffer thought it could skip copying
empty pages, but of course that does not work at all, because
subsequent blocks will be out of place.
Also fix it to acquire share lock on the source buffer. It *might*
be safe to not do that, but it's not very certain, and I don't think
this code deserves any benefit of the doubt.
Dilip Kumar, per complaint from me
Discussion: https://postgr.es/m/3679800.1659654066@sss.pgh.pa.us
Branch
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REL_15_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/811203d4aff505c414e4a9e8c57ea6bb3edfe92e
Modified Files
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src/backend/storage/buffer/bufmgr.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
