Implement the "lookaside" memory allocation cache. Use of this cache makes

the speed1.test script run about 15% faster.  Added new interfaces to
control the cache. (CVS 5488)

FossilOrigin-Name: e48f9697e9fea339e150ddc32940760027dd07d9

test/memsubsys1.test

@@ -11,7 +11,7 @@
 #
 # This file contains tests of the memory allocation subsystem
 #
-# $Id: memsubsys1.test,v 1.5 2008/07/25 13:39:08 drh Exp $
+# $Id: memsubsys1.test,v 1.6 2008/07/28 19:34:54 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -26,6 +26,7 @@ proc build_test_db {testname pragmas} {
   catch {db close}
   file delete -force test.db test.db-journal
   sqlite3 db test.db
+  sqlite3_db_config_lookaside db 0 0
   db eval $pragmas
   db eval {
     CREATE TABLE t1(x, y);
@@ -49,6 +50,7 @@ proc build_test_db {testname pragmas} {
 #
 db close
 sqlite3_shutdown
+sqlite3_config_lookaside 0 0
 sqlite3_initialize
 build_test_db memsubsys1-1 {PRAGMA page_size=1024}
 do_test memsubsys1-1.3 {
@@ -224,6 +226,7 @@ db close
 sqlite3_shutdown
 sqlite3_config_pagecache 0 0
 sqlite3_config_scratch 0 0
+sqlite3_config_lookaside 100 500
 sqlite3_initialize
 autoinstall_test_functions
 finish_test

test/speed1.test

@@ -11,11 +11,12 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this script is measuring executing speed.
 #
-# $Id: speed1.test,v 1.6 2008/07/24 23:34:07 drh Exp $
+# $Id: speed1.test,v 1.7 2008/07/28 19:34:54 drh Exp $
 #
 
 sqlite3_shutdown
 sqlite3_config_scratch 29000 1
+sqlite3_config_lookaside 1000 300
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
 speed_trial_init speed1