src/test/regress/expected/vacuum_parallel.out

   1 SET max_parallel_maintenance_workers TO 4;
   2 SET min_parallel_index_scan_size TO '128kB';
   3 -- Bug #17245: Make sure that we don't totally fail to VACUUM individual indexes that
   4 -- happen to be below min_parallel_index_scan_size during parallel VACUUM:
   5 CREATE TABLE parallel_vacuum_table (a int) WITH (autovacuum_enabled = off);
   6 INSERT INTO parallel_vacuum_table SELECT i from generate_series(1, 10000) i;
   7 -- Parallel VACUUM will never be used unless there are at least two indexes
   8 -- that exceed min_parallel_index_scan_size.  Create two such indexes, and
   9 -- a third index that is smaller than min_parallel_index_scan_size.
  10 CREATE INDEX regular_sized_index ON parallel_vacuum_table(a);
  11 CREATE INDEX typically_sized_index ON parallel_vacuum_table(a);
  12 -- Note: vacuum_in_leader_small_index can apply deduplication, making it ~3x
  13 -- smaller than the other indexes
  14 CREATE INDEX vacuum_in_leader_small_index ON parallel_vacuum_table((1));
  15 -- Verify (as best we can) that the cost model for parallel VACUUM
  16 -- will make our VACUUM run in parallel, while always leaving it up to the
  17 -- parallel leader to handle the vacuum_in_leader_small_index index:
  18 SELECT EXISTS (
  19 SELECT 1
  20 FROM pg_class
  21 WHERE oid = 'vacuum_in_leader_small_index'::regclass AND
  22   pg_relation_size(oid) <
  23   pg_size_bytes(current_setting('min_parallel_index_scan_size'))
  24 ) as leader_will_handle_small_index;
  25  leader_will_handle_small_index
  26 --------------------------------
  27  t
  28 (1 row)
  29
  30 SELECT count(*) as trigger_parallel_vacuum_nindexes
  31 FROM pg_class
  32 WHERE oid in ('regular_sized_index'::regclass, 'typically_sized_index'::regclass) AND
  33   pg_relation_size(oid) >=
  34   pg_size_bytes(current_setting('min_parallel_index_scan_size'));
  35  trigger_parallel_vacuum_nindexes
  36 ----------------------------------
  37                                 2
  38 (1 row)
  39
  40 -- Parallel VACUUM with B-Tree page deletions, ambulkdelete calls:
  41 DELETE FROM parallel_vacuum_table;
  42 VACUUM (PARALLEL 4, INDEX_CLEANUP ON) parallel_vacuum_table;
  43 -- Since vacuum_in_leader_small_index uses deduplication, we expect an
  44 -- assertion failure with bug #17245 (in the absence of bugfix):
  45 INSERT INTO parallel_vacuum_table SELECT i FROM generate_series(1, 10000) i;
  46 RESET max_parallel_maintenance_workers;
  47 RESET min_parallel_index_scan_size;
  48 -- Deliberately don't drop table, to get further coverage from tools like
  49 -- pg_amcheck in some testing scenarios