WL#11345: Increase default value of optimizer_trace_max_mem_size

The value of this variable is increased from 16kB to 1MB.

Author: roylyseng

mysql-test/r/mysqld--help-notwin.result

@@ -1482,7 +1482,7 @@ optimizer-switch index_merge=on,index_merge_union=on,index_merge_sort_union=on,i
 optimizer-trace 
 optimizer-trace-features greedy_search=on,range_optimizer=on,dynamic_range=on,repeated_subselect=on
 optimizer-trace-limit 1
-optimizer-trace-max-mem-size 16384
+optimizer-trace-max-mem-size 1048576
 optimizer-trace-offset -1
 parser-max-mem-size 18446744073709551615
 password-history 0

mysql-test/r/mysqld--help-win.result

@@ -1477,7 +1477,7 @@ optimizer-switch index_merge=on,index_merge_union=on,index_merge_sort_union=on,i
 optimizer-trace 
 optimizer-trace-features greedy_search=on,range_optimizer=on,dynamic_range=on,repeated_subselect=on
 optimizer-trace-limit 1
-optimizer-trace-max-mem-size 16384
+optimizer-trace-max-mem-size 1048576
 optimizer-trace-offset -1
 parser-max-mem-size 18446744073709551615
 password-history 0

mysql-test/suite/sys_vars/r/optimizer_trace_max_mem_size_basic.result

@@ -1,6 +1,6 @@
 SELECT @@global.optimizer_trace_max_mem_size;
 @@global.optimizer_trace_max_mem_size
-16384
+1048576
 SET @@global.optimizer_trace_max_mem_size=5;
 show global variables like 'optimizer_trace_max_mem_size';
 Variable_name	Value
@@ -10,13 +10,13 @@ VARIABLE_NAME	VARIABLE_VALUE
 optimizer_trace_max_mem_size	5
 select @@session.optimizer_trace_max_mem_size;
 @@session.optimizer_trace_max_mem_size
-16384
+1048576
 show session variables like 'optimizer_trace_max_mem_size';
 Variable_name	Value
-optimizer_trace_max_mem_size	16384
+optimizer_trace_max_mem_size	1048576
 select * from performance_schema.session_variables where variable_name='optimizer_trace_max_mem_size';
 VARIABLE_NAME	VARIABLE_VALUE
-optimizer_trace_max_mem_size	16384
+optimizer_trace_max_mem_size	1048576
 set session optimizer_trace_max_mem_size=10;
 select @@session.optimizer_trace_max_mem_size;
 @@session.optimizer_trace_max_mem_size
@@ -57,10 +57,10 @@ optimizer_trace_max_mem_size	5
 set global optimizer_trace_max_mem_size=default;
 select @@global.optimizer_trace_max_mem_size;
 @@global.optimizer_trace_max_mem_size
-16384
+1048576
 show global variables like 'optimizer_trace_max_mem_size';
 Variable_name	Value
-optimizer_trace_max_mem_size	16384
+optimizer_trace_max_mem_size	1048576
 set optimizer_trace_max_mem_size=1.1;
 ERROR 42000: Incorrect argument type to variable 'optimizer_trace_max_mem_size'
 set optimizer_trace_max_mem_size="foobar";

sql/sys_vars.cc

@@ -3154,7 +3154,7 @@ static Sys_var_ulong Sys_optimizer_trace_max_mem_size(
        "optimizer_trace_max_mem_size",
        "Maximum allowed cumulated size of stored optimizer traces",
        SESSION_VAR(optimizer_trace_max_mem_size), CMD_LINE(REQUIRED_ARG),
-       VALID_RANGE(0, ULONG_MAX), DEFAULT(1024*16), BLOCK_SIZE(1));
+       VALID_RANGE(0, ULONG_MAX), DEFAULT(1024*1024), BLOCK_SIZE(1));
 
 #endif