Disable vacuum page skipping in selected test cases.

By default VACUUM will skip pages that it can't immediately get
exclusive access to, which means that even activities as harmless
and unpredictable as checkpoint buffer writes might prevent a page
from being processed.  Ordinarily this is no big deal, but we have
a small number of test cases that examine the results of VACUUM's
processing and therefore will fail if the page of interest is skipped.
This seems to be the explanation for some rare buildfarm failures.
To fix, add the DISABLE_PAGE_SKIPPING option to the VACUUM commands
in tests where this could be an issue.

In passing, remove a duplicated query in pageinspect/sql/page.sql.

Back-patch as necessary (some of these cases are as old as v10).

Discussion: https://postgr.es/m/413923.1611006484@sss.pgh.pa.us

diff --git a/contrib/pageinspect/expected/page.out b/contrib/pageinspect/expected/page.out
index b6aea0124bbc118d16c0f13a36cce03f58a4142c..29ea91135be9067165c4e13a41ea922bca42cdb2 100644 (file)
--- a/contrib/pageinspect/expected/page.out
+++ b/contrib/pageinspect/expected/page.out
@@ -1,7 +1,7 @@
 CREATE EXTENSION pageinspect;
 CREATE TABLE test1 (a int, b int);
 INSERT INTO test1 VALUES (16777217, 131584);
-VACUUM test1;  -- set up FSM
+VACUUM (DISABLE_PAGE_SKIPPING) test1;  -- set up FSM
 -- The page contents can vary, so just test that it can be read
 -- successfully, but don't keep the output.
 SELECT octet_length(get_raw_page('test1', 'main', 0)) AS main_0;
@@ -83,18 +83,8 @@ SELECT * FROM fsm_page_contents(get_raw_page('test1', 'fsm', 0));
 (1 row)
 
 -- If we freeze the only tuple on test1, the infomask should
--- always be the same in all test runs. we show raw flags by
--- default: HEAP_XMIN_COMMITTED and HEAP_XMIN_INVALID.
-VACUUM FREEZE test1;
-SELECT t_infomask, t_infomask2, raw_flags, combined_flags
-FROM heap_page_items(get_raw_page('test1', 0)),
-     LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2);
- t_infomask | t_infomask2 |                         raw_flags                         |   combined_flags   
-------------+-------------+-----------------------------------------------------------+--------------------
-       2816 |           2 | {HEAP_XMIN_COMMITTED,HEAP_XMIN_INVALID,HEAP_XMAX_INVALID} | {HEAP_XMIN_FROZEN}
-(1 row)
-
--- output the decoded flag HEAP_XMIN_FROZEN instead
+-- always be the same in all test runs.
+VACUUM (FREEZE, DISABLE_PAGE_SKIPPING) test1;
 SELECT t_infomask, t_infomask2, raw_flags, combined_flags
 FROM heap_page_items(get_raw_page('test1', 0)),
      LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2);

diff --git a/contrib/pageinspect/sql/page.sql b/contrib/pageinspect/sql/page.sql
index bd049aeb247fc7eef494271bd2edcbb1afd548e1..9a3bc953862b50c7dae8049ab99e3c661040ba80 100644 (file)
--- a/contrib/pageinspect/sql/page.sql
+++ b/contrib/pageinspect/sql/page.sql
@@ -3,7 +3,7 @@ CREATE EXTENSION pageinspect;
 CREATE TABLE test1 (a int, b int);
 INSERT INTO test1 VALUES (16777217, 131584);
 
-VACUUM test1;  -- set up FSM
+VACUUM (DISABLE_PAGE_SKIPPING) test1;  -- set up FSM
 
 -- The page contents can vary, so just test that it can be read
 -- successfully, but don't keep the output.
@@ -32,15 +32,9 @@ SELECT tuple_data_split('test1'::regclass, t_data, t_infomask, t_infomask2, t_bi
 SELECT * FROM fsm_page_contents(get_raw_page('test1', 'fsm', 0));
 
 -- If we freeze the only tuple on test1, the infomask should
--- always be the same in all test runs. we show raw flags by
--- default: HEAP_XMIN_COMMITTED and HEAP_XMIN_INVALID.
-VACUUM FREEZE test1;
+-- always be the same in all test runs.
+VACUUM (FREEZE, DISABLE_PAGE_SKIPPING) test1;
 
-SELECT t_infomask, t_infomask2, raw_flags, combined_flags
-FROM heap_page_items(get_raw_page('test1', 0)),
-     LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2);
-
--- output the decoded flag HEAP_XMIN_FROZEN instead
 SELECT t_infomask, t_infomask2, raw_flags, combined_flags
 FROM heap_page_items(get_raw_page('test1', 0)),
      LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2);

diff --git a/contrib/pg_visibility/expected/pg_visibility.out b/contrib/pg_visibility/expected/pg_visibility.out
index 2abc1b5107a07d59f05103f7d28c0a9d986d866a..843550af58ba7bdbc66119a8b9eef4bb3d8bac98 100644 (file)
--- a/contrib/pg_visibility/expected/pg_visibility.out
+++ b/contrib/pg_visibility/expected/pg_visibility.out
@@ -104,7 +104,7 @@ ERROR:  "test_foreign_table" is not a table, materialized view, or TOAST table
 -- check some of the allowed relkinds
 create table regular_table (a int);
 insert into regular_table values (1), (2);
-vacuum regular_table;
+vacuum (disable_page_skipping) regular_table;
 select count(*) > 0 from pg_visibility('regular_table');
  ?column? 
 ----------
@@ -119,7 +119,7 @@ select count(*) > 0 from pg_visibility('regular_table');
 (1 row)
 
 create materialized view matview_visibility_test as select * from regular_table;
-vacuum matview_visibility_test;
+vacuum (disable_page_skipping) matview_visibility_test;
 select count(*) > 0 from pg_visibility('matview_visibility_test');
  ?column? 
 ----------
@@ -136,7 +136,7 @@ select count(*) > 0 from pg_visibility('matview_visibility_test');
 
 -- regular tables which are part of a partition *do* have visibility maps
 insert into test_partition values (1);
-vacuum test_partition;
+vacuum (disable_page_skipping) test_partition;
 select count(*) > 0 from pg_visibility('test_partition', 0);
  ?column? 
 ----------

diff --git a/contrib/pg_visibility/sql/pg_visibility.sql b/contrib/pg_visibility/sql/pg_visibility.sql
index c78b90521bfea96f088ab028f846619c866da43a..f1e917b26ce494ff18db5264f3ab841a910d8b87 100644 (file)
--- a/contrib/pg_visibility/sql/pg_visibility.sql
+++ b/contrib/pg_visibility/sql/pg_visibility.sql
@@ -70,13 +70,13 @@ select pg_truncate_visibility_map('test_foreign_table');
 -- check some of the allowed relkinds
 create table regular_table (a int);
 insert into regular_table values (1), (2);
-vacuum regular_table;
+vacuum (disable_page_skipping) regular_table;
 select count(*) > 0 from pg_visibility('regular_table');
 truncate regular_table;
 select count(*) > 0 from pg_visibility('regular_table');
 
 create materialized view matview_visibility_test as select * from regular_table;
-vacuum matview_visibility_test;
+vacuum (disable_page_skipping) matview_visibility_test;
 select count(*) > 0 from pg_visibility('matview_visibility_test');
 insert into regular_table values (1), (2);
 refresh materialized view matview_visibility_test;
@@ -84,7 +84,7 @@ select count(*) > 0 from pg_visibility('matview_visibility_test');
 
 -- regular tables which are part of a partition *do* have visibility maps
 insert into test_partition values (1);
-vacuum test_partition;
+vacuum (disable_page_skipping) test_partition;
 select count(*) > 0 from pg_visibility('test_partition', 0);
 select count(*) > 0 from pg_visibility_map('test_partition');
 select count(*) > 0 from pg_visibility_map_summary('test_partition');