PostgreSQL TODO List
====================
Current maintainer: Bruce Momjian (bruce@momjian.us)
-Last updated: Thu Sep 14 17:43:58 EDT 2006
+Last updated: Sat Sep 16 18:06:27 EDT 2006
The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html.
* Consider ways of storing rows more compactly on disk
- o Reorder physical storage order to reduce padding?
-
- This involves having the user-specified order of columns
- be different from the physical order. SELECT * would
- need to reorder the physical values to match the
- user-specified ordering.
-
- o Store disk pages with no alignment/padding?
-
- This necessitates adding CPU-required padding when moving
- rows from disk to memory.
-
o Support a smaller header for short variable-length fields?
- One idea is to store the header in network byte order (high bits
- first), and read the high bits to determine the header length.
- http://archives.postgresql.org/pgsql-hackers/2006-09/msg00848.php
+ One idea is to create zero-or-one-byte-header versions
+ of varlena data types. In involves setting the high-bit and
+ 0-127 length in the single-byte header, or clear the high bit
+ and store the 7-bit ASCII value in the rest of the byte.
+ The small-header versions have no alignment requirements.
+ http://archives.postgresql.org/pgsql-hackers/2006-09/msg01372.php
o Reduce the row header size?
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<h1><a name="section_1">PostgreSQL TODO List</a></h1>
<p>Current maintainer: Bruce Momjian (<a href="mailto:bruce@momjian.us">bruce@momjian.us</a>)<br/>
-Last updated: Thu Sep 14 17:43:58 EDT 2006
+Last updated: Sat Sep 16 18:06:27 EDT 2006
</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>.
</p>
</li><li>Consider ways of storing rows more compactly on disk
<ul>
- <li>Reorder physical storage order to reduce padding?
-<p> This involves having the user-specified order of columns
- be different from the physical order. SELECT * would
- need to reorder the physical values to match the
- user-specified ordering.
-</p>
- </li><li>Store disk pages with no alignment/padding?
-<p> This necessitates adding CPU-required padding when moving
- rows from disk to memory.
-</p>
- </li><li>Support a smaller header for short variable-length fields?
-<p> One idea is to store the header in network byte order (high bits
- first), and read the high bits to determine the header length.
- <a href="http://archives.postgresql.org/pgsql-hackers/2006-09/msg00848.php">http://archives.postgresql.org/pgsql-hackers/2006-09/msg00848.php</a>
+ <li>Support a smaller header for short variable-length fields?
+<p> One idea is to create zero-or-one-byte-header versions
+ of varlena data types. In involves setting the high-bit and
+ 0-127 length in the single-byte header, or clear the high bit
+ and store the 7-bit ASCII value in the rest of the byte.
+ The small-header versions have no alignment requirements.
+ <a href="http://archives.postgresql.org/pgsql-hackers/2006-09/msg01372.php">http://archives.postgresql.org/pgsql-hackers/2006-09/msg01372.php</a>
</p>
</li><li>Reduce the row header size?
</li></ul>
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