xref: /sqlite-3.40.0/test/cache.test (revision d230f648)
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 1.2 2007/04/06 21:42:22 drh Exp $
13
14set testdir [file dirname $argv0]
15source $testdir/tester.tcl
16
17ifcapable {!pager_pragmas} {
18  finish_test
19  return
20}
21
22proc pager_cache_size {db} {
23  set bt [btree_from_db $db]
24  array set stats [btree_pager_stats $bt]
25  return $stats(page)
26}
27
28do_test cache-1.1 {
29  pager_cache_size db
30} {0}
31
32do_test cache-1.2 {
33  execsql {
34    PRAGMA auto_vacuum=OFF;
35    CREATE TABLE abc(a, b, c);
36    INSERT INTO abc VALUES(1, 2, 3);
37  }
38  pager_cache_size db
39} {2}
40
41# At one point, repeatedly locking and unlocking the cache was causing
42# a resource leak of one page per repetition. The page wasn't actually
43# leaked, but would not be reused until the pager-cache was full (i.e.
44# 2000 pages by default).
45#
46# This tests that once the pager-cache is initialised, it can be locked
47# and unlocked repeatedly without internally allocating any new pages.
48#
49set cache_size [pager_cache_size db]
50for {set ii 0} {$ii < 10} {incr ii} {
51
52  do_test cache-1.3.$ii {
53    execsql {SELECT * FROM abc}
54    pager_cache_size db
55  } $::cache_size
56
57}
58
59finish_test
60