Use BUFFER_USAGE_LIMIT to reduce needed test table size

anarazel · anarazel · commit 322875597c0c · 2023-05-17T11:17:41.000-07:00
Using the minimum BUFFER_USAGE_LIMIT value, we can make one of the pg_stat_io test tables smaller while still causing reuses. Author: Melanie Plageman <melanieplageman@gmail.com> Discussion: https://postgr.es/m/CAAKRu_acc6iL4M3hvOTeztf_ZPpsB3Pqio5aVHgZ5q=Pi3BZKg@mail.gmail.com
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
@@ -1396,11 +1396,13 @@ SET wal_skip_threshold = '1 kB';
 SELECT sum(reuses) AS reuses, sum(reads) AS reads
   FROM pg_stat_io WHERE context = 'vacuum' \gset io_sum_vac_strategy_before_
 CREATE TABLE test_io_vac_strategy(a int, b int) WITH (autovacuum_enabled = 'false');
-INSERT INTO test_io_vac_strategy SELECT i, i from generate_series(1, 8000)i;
+INSERT INTO test_io_vac_strategy SELECT i, i from generate_series(1, 4500)i;
 -- Ensure that the next VACUUM will need to perform IO by rewriting the table
 -- first with VACUUM (FULL).
 VACUUM (FULL) test_io_vac_strategy;
-VACUUM (PARALLEL 0) test_io_vac_strategy;
+-- Use the minimum BUFFER_USAGE_LIMIT to cause reuses with the smallest table
+-- possible.
+VACUUM (PARALLEL 0, BUFFER_USAGE_LIMIT 128) test_io_vac_strategy;
 SELECT pg_stat_force_next_flush();
  pg_stat_force_next_flush 
 --------------------------
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
@@ -690,11 +690,13 @@ SET wal_skip_threshold = '1 kB';
 SELECT sum(reuses) AS reuses, sum(reads) AS reads
   FROM pg_stat_io WHERE context = 'vacuum' \gset io_sum_vac_strategy_before_
 CREATE TABLE test_io_vac_strategy(a int, b int) WITH (autovacuum_enabled = 'false');
-INSERT INTO test_io_vac_strategy SELECT i, i from generate_series(1, 8000)i;
+INSERT INTO test_io_vac_strategy SELECT i, i from generate_series(1, 4500)i;
 -- Ensure that the next VACUUM will need to perform IO by rewriting the table
 -- first with VACUUM (FULL).
 VACUUM (FULL) test_io_vac_strategy;
-VACUUM (PARALLEL 0) test_io_vac_strategy;
+-- Use the minimum BUFFER_USAGE_LIMIT to cause reuses with the smallest table
+-- possible.
+VACUUM (PARALLEL 0, BUFFER_USAGE_LIMIT 128) test_io_vac_strategy;
 SELECT pg_stat_force_next_flush();
 SELECT sum(reuses) AS reuses, sum(reads) AS reads
   FROM pg_stat_io WHERE context = 'vacuum' \gset io_sum_vac_strategy_after_
