# 2007 March 24

 #

 # The author disclaims copyright to this source code.  In place of

 # a legal notice, here is a blessing:

 #

 #    May you do good and not evil.

 #    May you find forgiveness for yourself and forgive others.

 #    May you share freely, never taking more than you give.

 #

 #***********************************************************************

 #

 # $Id: cache.test,v 1.4 2007/08/22 02:56:44 drh Exp $

 set testdir [file dirname $argv0]

 source $testdir/tester.tcl

 ifcapable {!pager_pragmas} {

   finish_test

   return

 }

 sqlite3_soft_heap_limit 0

 proc pager_cache_size {db} {

   set bt [btree_from_db $db]

   db_enter $db

   array set stats [btree_pager_stats $bt]

   db_leave $db

   return $stats(page)

 }

 do_test cache-1.1 {

   pager_cache_size db

 } {0}

 do_test cache-1.2 {

   execsql {

     PRAGMA auto_vacuum=OFF;

     CREATE TABLE abc(a, b, c);

     INSERT INTO abc VALUES(1, 2, 3);

   }

   pager_cache_size db

 } {2}

 # At one point, repeatedly locking and unlocking the cache was causing

 # a resource leak of one page per repetition. The page wasn't actually

 # leaked, but would not be reused until the pager-cache was full (i.e. 

 # 2000 pages by default).

 #

 # This tests that once the pager-cache is initialised, it can be locked

 # and unlocked repeatedly without internally allocating any new pages.

 #

 set cache_size [pager_cache_size db]

 for {set ii 0} {$ii < 10} {incr ii} {

   do_test cache-1.3.$ii {

     execsql {SELECT * FROM abc}

     pager_cache_size db

   } $::cache_size

 }

 sqlite3_soft_heap_limit $soft_limit

 finish_test