*** README.tsearch.orig	Fri Aug 23 10:13:47 2002
--- README.tsearch	Thu Aug 29 15:49:04 2002
***************
*** 6,11 ****
--- 6,13 ----
  
  CHANGES:
  
+ August 29, 2002
+         Space usage and using CLUSTER command documented
  August 22, 2002
  	Fix works with 'bad' queries
  August 13, 2002
***************
*** 286,293 ****
  and hardware).
  
  Collection is available for download from
! http://www.sai.msu.su/~megera/postgres/gist/tsearch/ 
! as mw_titles.gz (about 3Mb).
  
  0. install contrib/tsearch module
  1. createdb test
--- 288,295 ----
  and hardware).
  
  Collection is available for download from
! http://www.sai.msu.su/~megera/postgres/gist/tsearch/mw_titles.gz 
! (377905 titles from postgresql mailing lists, about 3Mb).
  
  0. install contrib/tsearch module
  1. createdb test
***************
*** 353,355 ****
--- 355,415 ----
  
  There are no visible difference between these 2 cases but your
  mileage may vary.
+ 
+ 
+ NOTES:
+ 
+ 1. The size of txtidx column should be lesser than size of corresponding column.
+    Below some real numbers from test database (link above).
+ 
+    a) After loading data
+    
+ -rw-------    1 postgres users    23191552 Aug 29 14:08 53016937
+ -rw-------    1 postgres users    81059840 Aug 29 14:08 52639027
+ 
+ Table titles (52639027) occupies 80Mb, index on txtidx column (53016937)
+ occupies 22Mb. Use contrib/oid2name to get mappings from oid to names.
+ After doing
+ 
+ test=# select title  into titles_tmp from titles;
+ SELECT
+ 
+ I got size of table 'titles' without txtidx field
+ 
+ -rw-------    1 postgres users    30105600 Aug 29 14:14 53016938
+ 
+ So, txtidx column itself occupies about 50Mb. 
+ 
+      b) after running 'vacuum full analyze' I got:
+ 
+ -rw-------    1 postgres users    30105600 Aug 29 14:26 53016938
+ -rw-------    1 postgres users    36880384 Aug 29 14:26 53016937
+ -rw-------    1 postgres users    51494912 Aug 29 14:26 52639027
+ 
+ 53016938 = titles_tmp
+ 
+ So, actual size of 'txtidx' field is 20 Mb !  "quod erat demonstrandum"
+ 
+ 2. CLUSTER command is highly recommended if you need fast searching.
+    For example:
+ 
+   test=# cluster t_idx on titles;
+ 
+   BUT ! In 7.2 CLUSTER command forgets about other indices and permissions,
+   so you need be carefull and rebuild these indices and restore permissions
+   after clustering. Also, clustering isn't dynamic, so you'd need to 
+   use CLUSTER from time to time. In 7.3 CLUSTER command should works
+   fine.
+ 
+   after clustering:
+ 
+ -rw-------    1 postgres users    23404544 Aug 29 14:59 53394850
+ -rw-------    1 postgres users    30105600 Aug 29 14:26 53016938
+ -rw-------    1 postgres users    50995200 Aug 29 14:45 53394845
+ pg@zen:/usr/local/pgsql/data/base/52638986$ oid2name -d test                 
+ All tables from database "test":
+ ---------------------------------
+ 53394850 = t_idx
+ 53394845 = titles
+ 53016938 = titles_tmp
+