# 2008 August 29

#

# 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.

#

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

#

# This file is focused on testing the pcache module.

#

# $Id: pcache.test,v 1.2 2008/09/05 05:29:09 danielk1977 Exp $

set testdir [file dirname $argv0]

source $testdir/tester.tcl

# The pcache module limits the number of pages available to purgeable

# caches to the sum of the 'cache_size' values for the set of open

# caches. This block of tests, pcache-1.*, test that the library behaves

# corrctly when it is forced to exceed this limit.

#

do_test pcache-1.1 {

  db close

  pcache_stats

} {current 0 max 0 min 0 recyclable 0}

do_test pcache-1.2 {

  sqlite3 db test.db

  execsql {

    PRAGMA cache_size=10;

    PRAGMA auto_vacuum=0;

  }

  pcache_stats

} {current 1 max 10 min 10 recyclable 1}

do_test pcache-1.3 {

  execsql {

    BEGIN;

    CREATE TABLE t1(a, b, c);

    CREATE TABLE t2(a, b, c);

    CREATE TABLE t3(a, b, c);

    CREATE TABLE t4(a, b, c);

    CREATE TABLE t5(a, b, c);

  }

  pcache_stats

} {current 6 max 10 min 10 recyclable 0}

do_test pcache-1.4 {

  execsql {

    CREATE TABLE t6(a, b, c);

    CREATE TABLE t7(a, b, c);

    CREATE TABLE t8(a, b, c);

    CREATE TABLE t9(a, b, c);

  }

  pcache_stats

} {current 10 max 10 min 10 recyclable 0}

do_test pcache-1.5 {

  sqlite3 db2 test.db

  execsql "PRAGMA cache_size=10" db2

  pcache_stats

} {current 11 max 20 min 20 recyclable 1}

do_test pcache-1.6 {

  execsql {

    BEGIN;

    SELECT * FROM sqlite_master;

  } db2

  pcache_stats

} {current 11 max 20 min 20 recyclable 0}

# At this point connection db2 has a read lock on the database file and a 

# single pinned page in its cache. Connection [db] is holding 10 dirty 

# pages. It cannot recycle them because of the read lock held by db2.

#

do_test pcache-1.6 {

  execsql {

    CREATE INDEX i1 ON t1(a, b);

    CREATE INDEX i2 ON t2(a, b);

    CREATE INDEX i3 ON t3(a, b);

    CREATE INDEX i4 ON t4(a, b);

    CREATE INDEX i5 ON t5(a, b);

    CREATE INDEX i6 ON t6(a, b);

    CREATE INDEX i7 ON t7(a, b);

    CREATE INDEX i8 ON t8(a, b);

    CREATE INDEX i9 ON t9(a, b);

  } 

  pcache_stats

} {current 20 max 20 min 20 recyclable 0}

do_test pcache-1.7 {

  execsql {

    CREATE TABLE t10(a, b, c);

  } 

  pcache_stats

} {current 21 max 20 min 20 recyclable 0}

# Rolling back the transaction held by db2 at this point releases a pinned

# page. Because the number of allocated pages is greater than the 

# configured maximum, this page should be freed immediately instead of

# recycled.

#

do_test pcache-1.8 {

  execsql {ROLLBACK} db2

  pcache_stats

} {current 20 max 20 min 20 recyclable 0}

do_test pcache-1.9 {

  execsql COMMIT

  pcache_stats

} {current 20 max 20 min 20 recyclable 20}

do_test pcache-1.10 {

  db2 close

  pcache_stats

} {current 10 max 10 min 10 recyclable 10}

do_test pcache-1.11 {

  execsql { PRAGMA cache_size = 20 }

  pcache_stats

} {current 10 max 20 min 10 recyclable 10}

do_test pcache-1.12 {

  execsql { 

    SELECT * FROM t1 ORDER BY a; SELECT * FROM t1;

    SELECT * FROM t2 ORDER BY a; SELECT * FROM t2;

    SELECT * FROM t3 ORDER BY a; SELECT * FROM t3;

    SELECT * FROM t4 ORDER BY a; SELECT * FROM t4;

    SELECT * FROM t5 ORDER BY a; SELECT * FROM t5;

    SELECT * FROM t6 ORDER BY a; SELECT * FROM t6;

    SELECT * FROM t7 ORDER BY a; SELECT * FROM t7;

    SELECT * FROM t8 ORDER BY a; SELECT * FROM t8;

    SELECT * FROM t9 ORDER BY a; SELECT * FROM t9;

  }

  pcache_stats

} {current 19 max 20 min 10 recyclable 19}

do_test pcache-1.13 {

  execsql { PRAGMA cache_size = 15 }

  pcache_stats

} {current 15 max 15 min 10 recyclable 15}

finish_test