Be lazier about partition tuple routing. It's not necessary to fully initialize the executor data structures for partitions to which no tuples are ever routed. Consider, for example, an INSERT statement that inserts only one row: it only cares about the partition to which that one row is routed. The new function ExecInitPartitionInfo performs the initialization in question only when a particular partition is about to receive a tuple. This includes creating, validating, and saving a pointer to the ResultRelInfo, setting up for speculative insertions, translating WCOs and initializing the resulting expressions, translating returning lists and building the appropriate projection information, and setting up a tuple conversion map.
One thing that's not deferred is locking the child partitions; that seems desirable but would need more thought. Still, testing shows that this makes single-row inserts significantly faster on a table with many partitions without harming the bulk-insert case. Amit Langote, reviewed by Etsuro Fujita, with a few changes by me Discussion: http://postgr.es/m/8975331d-d961-cbdd-f862-fdd3d97dc...@lab.ntt.co.jp Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/edd44738bc88148784899a8949519364d81d9ea8 Modified Files -------------- src/backend/commands/copy.c | 10 +- src/backend/executor/execPartition.c | 359 +++++++++++++++++++++++---------- src/backend/executor/nodeModifyTable.c | 133 +----------- src/include/executor/execPartition.h | 9 +- 4 files changed, 279 insertions(+), 232 deletions(-)