database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-10-27 00:12:01 +03:00
Code Activity

Change hash index creation so that rather than always establishing exactly

Browse Source 
two buckets at the start, we create a number of buckets appropriate for the
estimated size of the table.  This avoids a lot of expensive bucket-split
actions during initial index build on an already-populated table.

This is one of the two core ideas of Tom Raney and Shreya Bhargava's patch
to reduce hash index build time.  I'm committing it separately to make it
easier for people to test the effects of this separately from the effects
of their other core idea (pre-sorting the index entries by bucket number).
This commit is contained in:
Tom Lane
2008-03-15 20:46:31 +00:00
parent 4873c96ff3
commit c9a1cc694a
6 changed files with 70 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/include/access/hash.h
View File

@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/hash.h,v 1.84 2008/01/01 19:45:56 momjian Exp $
* $PostgreSQL: pgsql/src/include/access/hash.h,v 1.85 2008/03/15 20:46:31 tgl Exp $
*
* NOTES
* modeled after Margo Seltzer's hash implementation for unix.
@@ -298,7 +298,7 @@ extern void _hash_dropbuf(Relation rel, Buffer buf);
extern void _hash_wrtbuf(Relation rel, Buffer buf);
extern void _hash_chgbufaccess(Relation rel, Buffer buf, int from_access,
int to_access);
extern void _hash_metapinit(Relation rel);
extern void _hash_metapinit(Relation rel, double num_tuples);
extern void _hash_pageinit(Page page, Size size);
extern void _hash_expandtable(Relation rel, Buffer metabuf);