# 2007 September 10

#

# 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 contains tests that attempt to break the pcache module

#   by bombarding it with simultaneous requests from multiple threads.

#     

# $Id: thread003.test,v 1.4 2008/08/30 09:10:17 danielk1977 Exp $

set testdir [file dirname $argv0]

source $testdir/tester.tcl

source $testdir/thread_common.tcl

if {[info commands sqlthread] eq ""} {

  finish_test

  return

}

# Set up a couple of different databases full of pseudo-randomly 

# generated data.

#

do_test thread003.1.1 {

  execsql {

    BEGIN;

    CREATE TABLE t1(a, b, c);

  }

  for {set ii 0} {$ii < 5000} {incr ii} {

    execsql {INSERT INTO t1 VALUES($ii, randomblob(200), randomblob(200))}

  }

  execsql { 

    CREATE INDEX i1 ON t1(a, b); 

    COMMIT;

  }

} {}

do_test thread003.1.2 {

  expr {([file size test.db] / 1024) > 2000}

} {1}

do_test thread003.1.3 {

  db close

  file delete -force test2.db

  sqlite3 db test2.db

} {}

do_test thread003.1.4 {

  execsql {

    BEGIN;

    CREATE TABLE t1(a, b, c);

  }

  for {set ii 0} {$ii < 5000} {incr ii} {

    execsql {INSERT INTO t1 VALUES($ii, randomblob(200), randomblob(200))}

  }

  execsql { 

    CREATE INDEX i1 ON t1(a, b); 

    COMMIT;

  }

} {}

do_test thread003.1.5 {

  expr {([file size test.db] / 1024) > 2000}

} {1}

do_test thread003.1.6 {

  db close

} {}

# This test opens a connection on each of the large (>2MB) database files

# created by the previous block. The connections do not share a cache.

# Both "cache_size" parameters are set to 15, so there is a maximum of

# 30 pages available globally.

#

# Then, in separate threads, the databases are randomly queried over and

# over again. This will force the connections to recycle clean pages from

# each other. If there is a thread-safety problem, a segfault or assertion

# failure may eventually occur.

#

set nSecond 30

puts "Starting thread003.2 (should run for ~$nSecond seconds)"

do_test thread003.2 {

  foreach zFile {test.db test2.db} {

    set SCRIPT [format {

      set iEnd [expr {[clock_seconds] + %d}]

      set ::DB [sqlthread open %s]

      # Set the cache size to 15 pages per cache. 30 available globally.

      execsql { PRAGMA cache_size = 15 }

      while {[clock_seconds] < $iEnd} {

        set iQuery [expr {int(rand()*5000)}]

        execsql " SELECT * FROM t1 WHERE a = $iQuery "

      }

      sqlite3_close $::DB

      expr 1

    } $nSecond $zFile]

    unset -nocomplain finished($zFile)

    thread_spawn finished($zFile) $thread_procs $SCRIPT

  }

  foreach zFile {test.db test2.db} {

    if {![info exists finished($zFile)]} {

      vwait finished($zFile)

    }

  }

  expr 0

} {0}

# This test is the same as the test above, except that each thread also

# writes to the database. This causes pages to be moved back and forth 

# between the caches internal dirty and clean lists, which is another

# opportunity for a thread-related bug to present itself.

#

set nSecond 30

puts "Starting thread003.3 (should run for ~$nSecond seconds)"

do_test thread003.3 {

  foreach zFile {test.db test2.db} {

    set SCRIPT [format {

      set iStart [clock_seconds]

      set iEnd [expr {[clock_seconds] + %d}]

      set ::DB [sqlthread open %s]

      # Set the cache size to 15 pages per cache. 30 available globally.

      execsql { PRAGMA cache_size = 15 }

      while {[clock_seconds] < $iEnd} {

        set iQuery [expr {int(rand()*5000)}]

        execsql "SELECT * FROM t1 WHERE a = $iQuery"

        execsql "UPDATE t1 SET b = randomblob(200) 

                 WHERE a < $iQuery AND a > $iQuery + 20

        "

      }

      sqlite3_close $::DB

      expr 1

    } $nSecond $zFile]

    unset -nocomplain finished($zFile)

    thread_spawn finished($zFile) $thread_procs $SCRIPT

  }

  foreach zFile {test.db test2.db} {

    if {![info exists finished($zFile)]} {

      vwait finished($zFile)

    }

  }

  expr 0

} {0}

# In this test case, one thread is continually querying the database.

# The other thread does not have a database connection, but calls

# sqlite3_release_memory() over and over again.

#

set nSecond 30

puts "Starting thread003.3 (should run for ~$nSecond seconds)"

unset -nocomplain finished(1)

unset -nocomplain finished(2)

do_test thread003.4 {

  thread_spawn finished(1) $thread_procs [format {

    set iEnd [expr {[clock_seconds] + %d}]

    set ::DB [sqlthread open test.db]

    # Set the cache size to 15 pages per cache. 30 available globally.

    execsql { PRAGMA cache_size = 15 }

    while {[clock_seconds] < $iEnd} {

      set iQuery [expr {int(rand()*5000)}]

      execsql "SELECT * FROM t1 WHERE a = $iQuery"

    }

    sqlite3_close $::DB

    expr 1

  } $nSecond] 

  thread_spawn finished(2) [format {

    set iEnd [expr {[clock_seconds] + %d}]

    while {[clock_seconds] < $iEnd} {

      sqlite3_release_memory 1000

    }

  } $nSecond]

  foreach ii {1 2} {

    if {![info exists finished($ii)]} {

      vwait finished($ii)

    }

  }

  expr 0

} {0}

finish_test