Andres Freund 45e191e3aa Improve scalability of md.c for large relations.
So far md.c used a linked list of segments. That proved to be a problem
when processing large relations, because every smgr.c/md.c level access
to a page incurred walking through a linked list of all preceding
segments. Thus making accessing pages O(#segments).

Replace the linked list of segments hanging off SMgrRelationData with an
array of opened segments. That allows O(1) access to individual
segments, if they've previously been opened.

Discussion: <20140331101001.GE13135@alap3.anarazel.de>
Reviewed-By: Peter Geoghegan, Tom Lane (in an older version)
2016-09-08 17:18:46 -07:00
2016-05-06 14:02:44 -04:00
2016-09-06 12:00:00 -04:00
2016-08-15 13:49:49 -04:00
2016-08-15 13:49:49 -04:00
2016-01-02 13:33:40 -05:00
2014-02-12 18:16:17 -05:00
2011-02-15 06:52:12 +02:00

PostgreSQL Database Management System
=====================================

This directory contains the source code distribution of the PostgreSQL
database management system.

PostgreSQL is an advanced object-relational database management system
that supports an extended subset of the SQL standard, including
transactions, foreign keys, subqueries, triggers, user-defined types
and functions.  This distribution also contains C language bindings.

PostgreSQL has many language interfaces, many of which are listed here:

	http://www.postgresql.org/download

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

The latest version of this software may be obtained at
http://www.postgresql.org/download/.  For more information look at our
web site located at http://www.postgresql.org/.
Description
he World's Most Advanced Open Source Relational Database.
Readme 756 MiB
Languages
C 85.3%
PLpgSQL 6%
Perl 4.5%
Yacc 1.2%
Meson 0.7%
Other 2.1%