1select @@global.innodb_fatal_semaphore_wait_threshold;
2@@global.innodb_fatal_semaphore_wait_threshold
3600
4select @@session.innodb_fatal_semaphore_wait_threshold;
5ERROR HY000: Variable 'innodb_fatal_semaphore_wait_threshold' is a GLOBAL variable
6show global variables like 'innodb_fatal_semaphore_wait_threshold';
7Variable_name	Value
8innodb_fatal_semaphore_wait_threshold	600
9show session variables like 'innodb_fatal_semaphore_wait_threshold';
10Variable_name	Value
11innodb_fatal_semaphore_wait_threshold	600
12select * from information_schema.global_variables where variable_name='innodb_fatal_semaphore_wait_threshold';
13VARIABLE_NAME	VARIABLE_VALUE
14INNODB_FATAL_SEMAPHORE_WAIT_THRESHOLD	600
15select * from information_schema.session_variables where variable_name='innodb_fatal_semaphore_wait_threshold';
16VARIABLE_NAME	VARIABLE_VALUE
17INNODB_FATAL_SEMAPHORE_WAIT_THRESHOLD	600
18set global innodb_fatal_semaphore_wait_threshold=1;
19ERROR HY000: Variable 'innodb_fatal_semaphore_wait_threshold' is a read only variable
20set session innodb_fatal_semaphore_wait_threshold=1;
21ERROR HY000: Variable 'innodb_fatal_semaphore_wait_threshold' is a read only variable
22