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