xref: /sqlite-3.40.0/test/cache.test (revision 3aefabaf) 
1# 2007 March 24
2#
3# The author disclaims copyright to this source code.  In place of
4# a legal notice, here is a blessing:
5#
6#    May you do good and not evil.
7#    May you find forgiveness for yourself and forgive others.
8#    May you share freely, never taking more than you give.
9#
10#***********************************************************************
11#
12# $Id: cache.test,v 1.3 2007/08/12 20:07:59 drh Exp $
13
14set testdir [file dirname $argv0]
15source $testdir/tester.tcl
16
17ifcapable {!pager_pragmas} {
18  finish_test
19  return
20}
21sqlite3_soft_heap_limit 0
22
23proc pager_cache_size {db} {
24  set bt [btree_from_db $db]
25  array set stats [btree_pager_stats $bt]
26  return $stats(page)
27}
28
29do_test cache-1.1 {
30  pager_cache_size db
31} {0}
32
33do_test cache-1.2 {
34  execsql {
35    PRAGMA auto_vacuum=OFF;
36    CREATE TABLE abc(a, b, c);
37    INSERT INTO abc VALUES(1, 2, 3);
38  }
39  pager_cache_size db
40} {2}
41
42# At one point, repeatedly locking and unlocking the cache was causing
43# a resource leak of one page per repetition. The page wasn't actually
44# leaked, but would not be reused until the pager-cache was full (i.e.
45# 2000 pages by default).
46#
47# This tests that once the pager-cache is initialised, it can be locked
48# and unlocked repeatedly without internally allocating any new pages.
49#
50set cache_size [pager_cache_size db]
51for {set ii 0} {$ii < 10} {incr ii} {
52
53  do_test cache-1.3.$ii {
54    execsql {SELECT * FROM abc}
55    pager_cache_size db
56  } $::cache_size
57
58}
59sqlite3_soft_heap_limit $soft_limit
60
61finish_test
62