Movatterモバイル変換


[0]ホーム

URL:


Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

Sign up
Appearance settings

Commitcecde97

Browse files
committed
Update HOT README about when single-page vacuums happen.
1 parentf679cfe commitcecde97

File tree

1 file changed

+7
-1
lines changed

1 file changed

+7
-1
lines changed

‎src/backend/access/heap/README.HOT

Lines changed: 7 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
1-
$PostgreSQL: pgsql/src/backend/access/heap/README.HOT,v 1.6 2010/04/23 23:21:44rhaas Exp $
1+
$PostgreSQL: pgsql/src/backend/access/heap/README.HOT,v 1.7 2010/09/19 17:51:44momjian Exp $
22

33
Heap Only Tuples (HOT)
44
======================
@@ -246,6 +246,12 @@ scans reasonably sized, the maximum number of line pointers per page
246246
is arbitrarily capped at MaxHeapTuplesPerPage (the most tuples that
247247
could fit without HOT pruning).
248248

249+
Effectively, space reclamation happens during tuple retrieval when the
250+
page is nearly full (<10% free) and a buffer cleanup lock can be
251+
acquired. This means that UPDATE, DELETE, and SELECT can trigger space
252+
reclamation, but often not during INSERT ... VALUES because it does
253+
not retrieve a row.
254+
249255

250256
VACUUM
251257
------

0 commit comments

Comments
 (0)

[8]ページ先頭

©2009-2025 Movatter.jp