Обсуждение: pgsql: Fix GetNewTransactionId()'s interaction with xidVacLimit.

Fix GetNewTransactionId()'s interaction with xidVacLimit.

Commit ad308058 switched to returning a FullTransactionId, but
failed to load the potentially updated value in the case where
xidVacLimit is reached and we release and reacquire the lock.
Repair, closing bug #15727.

While reviewing that commit, also fix the size computation used
by EstimateTransactionStateSize() and switch to the mul_size()
macro traditionally used in such expressions.

Author: Thomas Munro
Reported-by: Roman Zharkov
Discussion: https://postgr.es/m/15727-0be246e7d852d229%40postgresql.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f7feb020c3d8d5aff24204af28359b99ee65bf8f

Modified Files
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src/backend/access/transam/varsup.c | 3 ++-
src/backend/access/transam/xact.c   | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)