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author | Tom Lane <tgl@sss.pgh.pa.us> | 2018-10-04 15:48:17 -0400 |
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committer | Tom Lane <tgl@sss.pgh.pa.us> | 2018-10-04 15:48:17 -0400 |
commit | d73f4c74dd34b19c19839f7ae09fb96442728509 (patch) | |
tree | c90ec26d55c24bfca08d92cb6b43873cb64ae848 /src/backend/executor/nodeLockRows.c | |
parent | 9ddef36278a9f676c07d0b4d9f33fa22e48ce3b5 (diff) | |
download | postgresql-d73f4c74dd34b19c19839f7ae09fb96442728509.tar.gz postgresql-d73f4c74dd34b19c19839f7ae09fb96442728509.zip |
In the executor, use an array of pointers to access the rangetable.
Instead of doing a lot of list_nth() accesses to es_range_table,
create a flattened pointer array during executor startup and index
into that to get at individual RangeTblEntrys.
This eliminates one source of O(N^2) behavior with lots of partitions.
(I'm not exactly convinced that it's the most important source, but
it's an easy one to fix.)
Amit Langote and David Rowley
Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
Diffstat (limited to 'src/backend/executor/nodeLockRows.c')
-rw-r--r-- | src/backend/executor/nodeLockRows.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/backend/executor/nodeLockRows.c b/src/backend/executor/nodeLockRows.c index 30de8a95ab8..6db345ae7ac 100644 --- a/src/backend/executor/nodeLockRows.c +++ b/src/backend/executor/nodeLockRows.c @@ -400,7 +400,7 @@ ExecInitLockRows(LockRows *node, EState *estate, int eflags) /* * Create workspace in which we can remember per-RTE locked tuples */ - lrstate->lr_ntables = list_length(estate->es_range_table); + lrstate->lr_ntables = estate->es_range_table_size; lrstate->lr_curtuples = (HeapTuple *) palloc0(lrstate->lr_ntables * sizeof(HeapTuple)); |