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.

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.
55af2a43 · Bruce Momjian · ce128c01 · 55af2a43 · 55af2a43
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Showing with 10 addition and 11 deletion

doc/TODO doc/TODO +5 -6

doc/src/FAQ/TODO.html doc/src/FAQ/TODO.html +5 -5

未找到文件。
--- 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


--- 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:           Tue Aug 30 19:25:23 EDT 2005
+Last updated:           Thu Sep  1 20:49:44 EDT 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>.
@@ -730,10 +730,6 @@ first.
 <p>  Moved tuples are invisible to other backends so they don't require a
  write lock. However, the read lock promotion to write lock could lead
  to deadlock situations.
-</p>
-  </li><li>Maintain a map of recently-expired rows
-<p>  This allows vacuum to target specific pages for possible free space 
-  without requiring a sequential scan.
 </p>
  </li><li>Auto-fill the free space map by scanning the buffer cache or by
  checking pages written by the background writer
@@ -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.
 </p>
  </li><li>%Add system view to show free space map contents
  </li><li>Auto-vacuum