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Avoid edge case in pg_visibility test with small shared_buffers

Since82a4eda we can bulk extend relations. The bulk relation extensionlogic has a heuristic component. Normally the heurstic does not trigger in theoccasionally-failing test case, as the relation is only extended once. Butwith very small shared_buffers the limits for the number of buffers pinned atonce prevent the extension from happening at once. With the second "bulk"extension, the heuristic kicks in, and the relation ends up one block bigger.That's ok from a correctness perspective, but changes the results of the testquery due to one additional block.We discussed a few more expansive fixes, but for now have decided to avoidthis by making the table a bit smaller.Author: Heikki Linnakangas <hlinnaka@iki.fi>Reported-by:Discussion:https://postgr.es/m/29c74104-210b-ef39-2522-27a6aa7a704f@iki.fiDiscussion:https://postgr.es/m/20230916000011.2ugpkkkp7bpp4cfh@awork3.anarazel.deBackpatch: 16-, where the new relation extension logic was added

1 parent90677b5 commit408209dCopy full SHA for 408209d

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2 files changed

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contrib/pg_visibility
- expected
  - pg_visibility.out
- sql
  - pg_visibility.sql

2 files changed

-8

lines changed

`‎contrib/pg_visibility/expected/pg_visibility.out`

Lines changed: 1 addition & 2 deletions

Original file line number	Diff line number	Diff line change
`@@ -217,8 +217,7 @@ select * from pg_visibility_map('copyfreeze');`
`217`	`217`	`-------+-------------+------------`
`218`	`218`	`0 \| t \| t`
`219`	`219`	`1 \| t \| t`
`220`		`- 2 \| t \| t`
`221`		`-(3 rows)`
	`220`	`+(2 rows)`
`222`	`221`
`223`	`222`	`select * from pg_check_frozen('copyfreeze');`
`224`	`223`	`t_ctid`

`‎contrib/pg_visibility/sql/pg_visibility.sql`

Lines changed: 0 additions & 6 deletions

Original file line number	Diff line number	Diff line change
`@@ -108,12 +108,6 @@ copy copyfreeze from stdin freeze;`
`108`	`108`	`4'4'`
`109`	`109`	`5'5'`
`110`	`110`	`6'6'`
`111`		`-7'7'`
`112`		`-8'8'`
`113`		`-9'9'`
`114`		`-10'10'`
`115`		`-11'11'`
`116`		`-12'12'`
`117`	`111`	`\.`
`118`	`112`	`commit;`
`119`	`113`	`select*from pg_visibility_map('copyfreeze');`

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Commit408209d

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2 files changed

2 files changed

`‎contrib/pg_visibility/expected/pg_visibility.out`

`‎contrib/pg_visibility/sql/pg_visibility.sql`

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