flush status;
SET @saved_thread_cache_size = @@global.thread_cache_size;
set global thread_cache_size = 0;
show variables like "thread_cache_size";
Variable_name	Value
thread_cache_size	0
connect  con1, localhost, root, , ;
connect  con2, localhost, root, , ;
connection default;
select @id_increment;
@id_increment
1
select @thread_id_increment;
@thread_id_increment
1
disconnect con2;
connection default;
connect  con3, localhost, root, , ;
disconnect con3;
disconnect con1;
connection default;
select @id_increment;
@id_increment
1
select @thread_id_increment;
@thread_id_increment
1
set global thread_cache_size = 100;
show variables like "thread_cache_size";
Variable_name	Value
thread_cache_size	100
connect  con1, localhost, root, , ;
connect  con2, localhost, root, , ;
connection default;
select @id_increment;
@id_increment
1
select @thread_id_increment;
@thread_id_increment
1
disconnect con2;
connection default;
connect  con3, localhost, root, , ;
disconnect con3;
disconnect con1;
connection default;
select @id_increment;
@id_increment
1
select @thread_id_increment;
@thread_id_increment
1
set global thread_cache_size = @saved_thread_cache_size;
show status like "performance_schema_thread%";
Variable_name	Value
Performance_schema_thread_classes_lost	0
Performance_schema_thread_instances_lost	0