projects / postgresql.git / commit
summary | shortlog | log | commit | commitdiff | tree
(parent: 53367e6) | patch
Adjust cost model for HashAgg that spills to disk.
authorJeff Davis <jdavis@postgresql.org>
Mon, 7 Sep 2020 20:31:59 +0000 (13:31 -0700)
committerJeff Davis <jdavis@postgresql.org>
Mon, 7 Sep 2020 20:31:59 +0000 (13:31 -0700)
commita547e6867527ca16628a3fb1cf3ef6f785210a31
tree1d6c0862569114cf9061f8038b9d30cf56262a9dtree
parent53367e6c62e3111eccdd578a3fa607c48c3e1fb6commit | diff
Adjust cost model for HashAgg that spills to disk.

Tomas Vondra observed that the IO behavior for HashAgg tends to be
worse than for Sort. Penalize HashAgg IO costs accordingly.

Also, account for the CPU effort of spilling the tuples and reading
them back.

Discussion: https://postgr.es/m/20200906212112.nzoy5ytrzjjodpfh@development
Reviewed-by: Tomas Vondra
Backpatch-through: 13
src/backend/optimizer/path/costsize.c diff | blob | blame | history
This is the main PostgreSQL git repository.