mysql 怎样flush global variable?

tanhy

在mysql 5.0 要怎样reset global variables?
flush status 只能reset thread variables

soonyu

are you try to say something like this ?

mysql>set @@wait_timeout=29000;

after it set, you can check
mysql> show variables like 'wait%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout  | 29000 |
+---------------+-------+

it will change immediately, but when you restart the mysql server, the figure reset to older figure.

tanhy

我需要reset 的是status variable
我正做performance tuning, 要知道set 了一些server setting后有什么effect
比如说
show status；
会show 我们一些server的status variable，比如有多少read request hits physical page
我需要reset 这些status variables

tanhy

找到了，　flush status
不过要restart service 才能看到effect