Release memory allocated by dependency_degree Calculating degree of a functional dependency may allocate a lot of memory - we have released mot of the explicitly allocated memory, but e.g. detoasted varlena values were left behind. That may be an issue, because we consider a lot of dependencies (all combinations), and the detoasting may happen for each one again.
Fixed by calling dependency_degree() in a dedicated context, and resetting it after each call. We only need the calculated dependency degree, so we don't need to copy anything. Backpatch to PostgreSQL 10, where extended statistics were introduced. Backpatch-through: 10 Discussion: https://www.postgresql.org/message-id/20210915200928.GP831%40telsasoft.com Branch ------ REL_10_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/d77e085afd52e9023075288ba95cf3280e273c2d Modified Files -------------- src/backend/statistics/dependencies.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-)
