postgres.git / summary / log / commit / refs
commit 113ece8f3d704cdcf20f2865d1ea8964159ee476
Author: Bruce Momjian <bruce@momjian.us>
Date: Thu Dec 01 22:30:43 2005 +0000
First released in: 8.2.0
Add all heap page rows visible bitmap idea:
< the heap. One way to allow this is to set a bit to index tuples
> the heap. One way to allow this is to set a bit on index tuples
< be cleared when a heap tuple is expired.
<
> be cleared when a heap tuple is expired. Another idea is to maintain
> a bitmap of heap pages where all rows are visible to all backends,
> and allow index lookups to reference that bitmap to avoid heap
> lookups, perhaps the same bitmap we might add someday to determine
> which heap pages need vacuuming.
doc/TODO | 11 +++++++----
doc/src/FAQ/TODO.html | 10 +++++++---
2 files changed, 14 insertions(+), 7 deletions(-)
diff --git a/doc/TODO b/doc/TODO
index 22c6e3c4614..c3bf43a5f85 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: Thu Dec 1 17:12:27 EST 2005
+Last updated: Thu Dec 1 17:30:23 EST 2005
The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html.
@@ -859,11 +859,14 @@ Cache Usage
Currently indexes do not have enough tuple visibility information
to allow data to be pulled from the index without also accessing
- the heap. One way to allow this is to set a bit to index tuples
+ the heap. One way to allow this is to set a bit on index tuples
to indicate if a tuple is currently visible to all transactions
when the first valid heap lookup happens. This bit would have to
- be cleared when a heap tuple is expired.
-
+ be cleared when a heap tuple is expired. Another idea is to maintain
+ a bitmap of heap pages where all rows are visible to all backends,
+ and allow index lookups to reference that bitmap to avoid heap
+ lookups, perhaps the same bitmap we might add someday to determine
+ which heap pages need vacuuming.
* Consider automatic caching of queries at various levels:
diff --git a/doc/src/FAQ/TODO.html b/doc/src/FAQ/TODO.html
index 7bb7cd28420..7e4961eaa7b 100644
--- a/doc/src/FAQ/TODO.html
+++ b/doc/src/FAQ/TODO.html
@@ -8,7 +8,7 @@
<body bgcolor="#FFFFFF" text="#000000" link="#FF0000" vlink="#A00000" alink="#0000FF">
<h1><a name="section_1">PostgreSQL TODO List</a></h1>
<p>Current maintainer: Bruce Momjian (<a href="mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</a>)<br/>
-Last updated: Thu Dec 1 17:12:27 EST 2005
+Last updated: Thu Dec 1 17:30:23 EST 2005
</p>
<p>The most recent version of this document can be viewed at<br/>
<a href="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
@@ -778,10 +778,14 @@ first.
</li><li>Allow data to be pulled directly from indexes
<p> Currently indexes do not have enough tuple visibility information
to allow data to be pulled from the index without also accessing
- the heap. One way to allow this is to set a bit to index tuples
+ the heap. One way to allow this is to set a bit on index tuples
to indicate if a tuple is currently visible to all transactions
when the first valid heap lookup happens. This bit would have to
- be cleared when a heap tuple is expired.
+ be cleared when a heap tuple is expired. Another idea is to maintain
+ a bitmap of heap pages where all rows are visible to all backends,
+ and allow index lookups to reference that bitmap to avoid heap
+ lookups, perhaps the same bitmap we might add someday to determine
+ which heap pages need vacuuming.
</p>
</li><li>Consider automatic caching of queries at various levels:
<ul>
[parent: 915fb7f687bd]