SET @start_global_value = @@global.thread_pool_size;
select @@global.thread_pool_size;
@@global.thread_pool_size
#
select @@session.thread_pool_size;
ERROR HY000: Variable 'thread_pool_size' is a GLOBAL variable
show global variables like 'thread_pool_size';
Variable_name	Value
thread_pool_size	#
show session variables like 'thread_pool_size';
Variable_name	Value
thread_pool_size	#
select * from information_schema.global_variables where variable_name='thread_pool_size';
VARIABLE_NAME	VARIABLE_VALUE
THREAD_POOL_SIZE	#
select * from information_schema.session_variables where variable_name='thread_pool_size';
VARIABLE_NAME	VARIABLE_VALUE
THREAD_POOL_SIZE	#
set global thread_pool_size=1;
select @@global.thread_pool_size;
@@global.thread_pool_size
1
set global thread_pool_size=128;
select @@global.thread_pool_size;
@@global.thread_pool_size
128
set session thread_pool_size=1;
ERROR HY000: Variable 'thread_pool_size' is a GLOBAL variable and should be set with SET GLOBAL
set global thread_pool_size=1.1;
ERROR 42000: Incorrect argument type to variable 'thread_pool_size'
set global thread_pool_size=1e1;
ERROR 42000: Incorrect argument type to variable 'thread_pool_size'
set global thread_pool_size="foo";
ERROR 42000: Incorrect argument type to variable 'thread_pool_size'
set global thread_pool_size=-1;
Warnings:
Warning	1292	Truncated incorrect thread_pool_size value: '-1'
set global thread_pool_size=100000;
Warnings:
Warning	1292	Truncated incorrect thread_pool_size value: '100000'
SET @@global.thread_pool_size = @start_global_value;
