SELECT
@@global.wait_timeout, @@global.thread_pool_max_threads, @@global.thread_pool_size,
@@global.thread_pool_oversubscribe,  @@global.thread_pool_stall_limit
INTO
@_wait_timeout,@_thread_pool_max_threads,@_thread_pool_size,
@_thread_pool_oversubscribe,@_thread_pool_stall_limit;
SET @@global.wait_timeout=1,
@@global.thread_pool_max_threads=2,
@@global.thread_pool_size=1,
@@global.thread_pool_oversubscribe=1,
@@global.thread_pool_stall_limit=10;
connect  c1, localhost, root,,;
connect  c2, localhost, root,,;
connect  c3, localhost, root,,;
connection c1;
select sleep(1.1);
connection c2;
select sleep(1.1);
connection c3;
select sleep(1.1);
connection default;
select sleep(1.1);
connection c1;
sleep(1.1)
0
connection c2;
sleep(1.1)
0
connection c3;
sleep(1.1)
0
connection default;
sleep(1.1)
0
disconnect c1;
disconnect c2;
disconnect c3;
connection default;
SET @@global.wait_timeout=@_wait_timeout,
@@global.thread_pool_max_threads=@_thread_pool_max_threads,
@@global.thread_pool_size=@_thread_pool_size,
@@global.thread_pool_oversubscribe=@_thread_pool_oversubscribe,
@@global.thread_pool_stall_limit=@_thread_pool_stall_limit;