Comment 1 for bug 1202940

at line 401 tuning-primer attempt to get join_buffer_size doing:

mysql -Bse "show variables like 'join_buffer%'"

but unlike myslq, MariaDB have two variables that match:

join_buffer_size
join_buffer_space_limit

so, to fix, simply change line 943 from:

mysql_variable \'join_buffer%\' join_buffer_size

to

mysql_variable \'join_buffer_size%\' join_buffer_size