PostgreSQL TODO List

====================

Current maintainer:Bruce Momjian (bruce@momjian.us)

Last updated:Fri Jun1 22:46:01 EDT 2007

Last updated:Sat Jun2 07:27:46 EDT 2007

The most recent version of this document can be viewed at

http://www.postgresql.org/docs/faqs.TODO.html.

Cache Usage

===========

* Allow free-behind capability for large sequential scans to avoid

kernel cache spoiling

Posix_fadvise() can control both sequential/random file caching and

free-behind behavior, but it is unclear how the setting affects other

backends that also have the file open, and the feature is not supported

on all operating systems.

* Speed up COUNT(*)

We could use a fixed row count and a +/- count to follow MVCC

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<h1><aname="section_1">PostgreSQL TODO List</a></h1>

<p>Current maintainer: Bruce Momjian (<ahref="mailto:bruce@momjian.us">bruce@momjian.us</a>)<br/>

Last updated:Fri Jun1 22:46:01 EDT 2007

Last updated:Sat Jun2 07:27:46 EDT 2007

<p>The most recent version of this document can be viewed at<br/>

<ahref="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.

<h1><aname="section_14">Cache Usage</a></h1>

<li>Speed up COUNT(*)

<li>Allow free-behind capability for large sequential scans to avoid

kernel cache spoiling

<p> Posix_fadvise() can control both sequential/random file caching and

free-behind behavior, but it is unclear how the setting affects other

backends that also have the file open, and the feature is not supported

on all operating systems.

</li><li>Speed up COUNT(*)

<p> We could use a fixed row count and a +/- count to follow MVCC

visibility rules, or a single cached value could be used and

invalidated if anyone modifies the table. Another idea is to