MySQL SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded
If you wan't to check the queries/s in live you can use the mysqladmin tool with some options:

[root@db-prod-01 ~]# mysqladmin extended-status -uroot -p -i 1 -r | grep 'Com_insert '
Enter password: 
| Com_insert                            | 59863746      |
| Com_insert                            | 1             |
| Com_insert                            | 2             |
| Com_insert                            | 9             |
| Com_insert                            | 2             |
| Com_insert                            | 2             |
| Com_insert                            | 3             |
| Com_insert                            | 2             |
| Com_insert                            | 3             |
| Com_insert                            | 6             |



extended-status: return the result of SHOW GLOBAL STATUS;
-i 1 -r:  Execute the SHOW GLOBAL STATUS; every second (one line by second)
| grep 'Com_insert': Shows only INSERTS statements


Note that Com_insert is a cumulativ counter the first line shows the nominal counter value and at each iteration of mysqladmin, a substraction is made to show you how there were insertions during the time you setted (here -i 1 is each 1 second).

By the way, if you want some infos for your error (1205) it's the InnoDB Engine that should check because it's the only way to see which of your query (or queries) is/are stucking your DB.

You can find infos on current and past transactions that lock your DB with:

SHOW ENGINE INNODB STATUS; -- In a MySQL prompt


Max.