From 55af2a43372f0fe9da312b8db35874a18a226143 Mon Sep 17 00:00:00 2001
From: Bruce Momjian
Date: Fri, 2 Sep 2005 00:49:57 +0000
Subject: [PATCH] Duplicate:
< * Maintain a map of recently-expired rows
<
< This allows vacuum to target specific pages for possible free space
< without requiring a sequential scan.
<
Update entry:
> One complexity is that index entries still have to be vacuumed, and
> doing this without an index scan (by using the heap values to find the
> index entry) might be slow and unreliable, especially for user-defined
> index functions.
---
doc/TODO | 11 +++++------
doc/src/FAQ/TODO.html | 10 +++++-----
2 files changed, 10 insertions(+), 11 deletions(-)
diff --git a/doc/TODO b/doc/TODO
index ab145472bd..7c88a4afe3 100644
--- a/doc/TODO
+++ b/doc/TODO
@@ -2,7 +2,7 @@
PostgreSQL TODO List
====================
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
-Last updated: Tue Aug 30 19:25:23 EDT 2005
+Last updated: Thu Sep 1 20:49:44 EDT 2005
The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html.
@@ -810,11 +810,6 @@ Vacuum
write lock. However, the read lock promotion to write lock could lead
to deadlock situations.
-* Maintain a map of recently-expired rows
-
- This allows vacuum to target specific pages for possible free space
- without requiring a sequential scan.
-
* Auto-fill the free space map by scanning the buffer cache or by
checking pages written by the background writer
* Create a bitmap of pages that need vacuuming
@@ -823,6 +818,10 @@ Vacuum
writer or some other process record pages that have expired rows, then
VACUUM can look at just those pages rather than the entire table. In
the event of a system crash, the bitmap would probably be invalidated.
+ One complexity is that index entries still have to be vacuumed, and
+ doing this without an index scan (by using the heap values to find the
+ index entry) might be slow and unreliable, especially for user-defined
+ index functions.
* %Add system view to show free space map contents
diff --git a/doc/src/FAQ/TODO.html b/doc/src/FAQ/TODO.html
index 734597a964..f24c9a5605 100644
--- a/doc/src/FAQ/TODO.html
+++ b/doc/src/FAQ/TODO.html
@@ -8,7 +8,7 @@
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
-Last updated: Tue Aug 30 19:25:23 EDT 2005
+Last updated: Thu Sep 1 20:49:44 EDT 2005
The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html.
@@ -731,10 +731,6 @@ first.
write lock. However, the read lock promotion to write lock could lead
to deadlock situations.
- Maintain a map of recently-expired rows
- This allows vacuum to target specific pages for possible free space
- without requiring a sequential scan.
-
Auto-fill the free space map by scanning the buffer cache or by
checking pages written by the background writer
Create a bitmap of pages that need vacuuming
@@ -742,6 +738,10 @@ first.
writer or some other process record pages that have expired rows, then
VACUUM can look at just those pages rather than the entire table. In
the event of a system crash, the bitmap would probably be invalidated.
+ One complexity is that index entries still have to be vacuumed, and
+ doing this without an index scan (by using the heap values to find the
+ index entry) might be slow and unreliable, especially for user-defined
+ index functions.
%Add system view to show free space map contents
Auto-vacuum
--
2.11.0