Improve performance of index-only scans with many index columns. StoreIndexTuple was a loop over index_getattr, which is O(N^2) if the index columns are variable-width, and the performance impact is already quite visible at ten columns. The obvious move is to replace that with a call to index_deform_tuple ... but that's *also* a loop over index_getattr. Improve it to be essentially a clone of heap_deform_tuple.
(There are a few other places that loop over all index columns with index_getattr, and perhaps should be changed likewise, but most of them don't seem performance-critical. Anyway, the rest would mostly only be interested in the index key columns, which there aren't likely to be so many of. Wide index tuples are a new thing with INCLUDE.) Konstantin Knizhnik Discussion: https://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/80b9e9c4664a020ebd14889046bd8d22a17d1ca6 Modified Files -------------- src/backend/access/common/indextuple.c | 69 ++++++++++++++++++++++++++++++-- src/backend/executor/nodeIndexonlyscan.c | 20 ++++----- 2 files changed, 72 insertions(+), 17 deletions(-)
