diff options
| author | Robert Haas | 2017-12-05 19:35:33 +0000 |
|---|---|---|
| committer | Robert Haas | 2017-12-05 19:35:33 +0000 |
| commit | 2c09a5c12a66087218c7f8cba269cd3de51b9b82 (patch) | |
| tree | 952f7dc04e00e3226f2fc272b2107dec6b2061ff /src/test | |
| parent | 5bcf389ecfd40daf92238e1abbff4fc4d3f18b33 (diff) | |
Fix accumulation of parallel worker instrumentation.
When a Gather or Gather Merge node is started and stopped multiple
times, the old code wouldn't reset the shared state between executions,
potentially resulting in dramatically inflated instrumentation data
for nodes beneath it. (The per-worker instrumentation ended up OK,
I think, but the overall totals were inflated.)
Report by hubert depesz lubaczewski. Analysis and fix by Amit Kapila,
reviewed and tweaked a bit by me.
Discussion: http://postgr.es/m/20171127175631.GA405@depesz.com
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/select_parallel.out | 21 | ||||
| -rw-r--r-- | src/test/regress/sql/select_parallel.sql | 7 |
2 files changed, 28 insertions, 0 deletions
diff --git a/src/test/regress/expected/select_parallel.out b/src/test/regress/expected/select_parallel.out index d1d5b228ce0..b748c98c915 100644 --- a/src/test/regress/expected/select_parallel.out +++ b/src/test/regress/expected/select_parallel.out @@ -378,7 +378,28 @@ select count(*) from bmscantest where a>1; 99999 (1 row) +-- test accumulation of stats for parallel node reset enable_seqscan; +alter table tenk2 set (parallel_workers = 0); +explain (analyze, timing off, summary off, costs off) + select count(*) from tenk1, tenk2 where tenk1.hundred > 1 + and tenk2.thousand=0; + QUERY PLAN +-------------------------------------------------------------------------- + Aggregate (actual rows=1 loops=1) + -> Nested Loop (actual rows=98000 loops=1) + -> Seq Scan on tenk2 (actual rows=10 loops=1) + Filter: (thousand = 0) + Rows Removed by Filter: 9990 + -> Gather (actual rows=9800 loops=10) + Workers Planned: 4 + Workers Launched: 4 + -> Parallel Seq Scan on tenk1 (actual rows=1960 loops=50) + Filter: (hundred > 1) + Rows Removed by Filter: 40 +(11 rows) + +alter table tenk2 reset (parallel_workers); reset enable_indexscan; reset enable_hashjoin; reset enable_mergejoin; diff --git a/src/test/regress/sql/select_parallel.sql b/src/test/regress/sql/select_parallel.sql index bb4e34adbe0..00df92779c6 100644 --- a/src/test/regress/sql/select_parallel.sql +++ b/src/test/regress/sql/select_parallel.sql @@ -149,7 +149,14 @@ insert into bmscantest select r, 'fooooooooooooooooooooooooooooooooooooooooooooo create index i_bmtest ON bmscantest(a); select count(*) from bmscantest where a>1; +-- test accumulation of stats for parallel node reset enable_seqscan; +alter table tenk2 set (parallel_workers = 0); +explain (analyze, timing off, summary off, costs off) + select count(*) from tenk1, tenk2 where tenk1.hundred > 1 + and tenk2.thousand=0; +alter table tenk2 reset (parallel_workers); + reset enable_indexscan; reset enable_hashjoin; reset enable_mergejoin; |