Description:
I seem some describes about valiables of InnoDB FullText-Search has differences from server behavior.
o- innodb_ft_cache_size is described "Dynamic Variable" but It can't be changed dynamically.
o- Default Value of innodb_ft_cache_size is described 33554432(32MiB) but it shows 32000000(32 * 10^6).
o- innodb_ft_max_token_size is described "Dynamic Variable" but It can't be changed dynamically.
o- innodb_ft_min_token_size is described "Dynamic Variable" but It can't be changed dynamically.
o- innodb_ft_sort_pll_degree is described "Dynamic Variable" but It can't be changed dynamically.
How to repeat:
mysql> show variables like 'innodb_ft%';
+---------------------------------+----------+
| Variable_name | Value |
+---------------------------------+----------+
| innodb_ft_aux_table | |
| innodb_ft_cache_size | 32000000 |
| innodb_ft_enable_diag_print | OFF |
| innodb_ft_enable_stopword | ON |
| innodb_ft_max_token_size | 84 |
| innodb_ft_min_token_size | 3 |
| innodb_ft_num_word_optimize | 2000 |
| innodb_ft_server_stopword_table | |
| innodb_ft_sort_pll_degree | 2 |
| innodb_ft_user_stopword_table | |
+---------------------------------+----------+
10 rows in set (0.03 sec)
mysql> set global innodb_ft_cache_size = 16 * 1024 * 1024;
ERROR 1238 (HY000): Variable 'innodb_ft_cache_size' is a read only variable
mysql> set global innodb_ft_max_token_size = 10;
ERROR 1238 (HY000): Variable 'innodb_ft_max_token_size' is a read only variable
mysql> set global innodb_ft_min_token_size = 1;
ERROR 1238 (HY000): Variable 'innodb_ft_min_token_size' is a read only variable
mysql> set global innodb_ft_sort_pll_degree = 32;
ERROR 1238 (HY000): Variable 'innodb_ft_sort_pll_degree' is a read only variable
Suggested fix:
Maybe document's mistake.