All queries waiting for query cache lock

I'm managing a e-commerce site which uses a popular online shopping cart software running on MySQL 5.6. Yesterday I noticed that SHOW PROCESSLIST reports that 990 of 1000 queries are waiting for a query cache lock: mysql> show processlist; +----------+------------+---------------------+-------------+---------+------+--------------------------------+------------------------------------------------------------------------------------------------------+ | Id | User | Host | db | Command | Time | State | Info | +----------+------------+---------------------+-------------+---------+------+--------------------------------+------------------------------------------------------------------------------------------------------+ | 12224065 | sqluser | 10.13.13.13:21716 | mydatabase | Query | 0 | Waiting for query cache lock | SELECT data FROM mytable WHERE foo = 'bar' | (...) However, the Time is always 0 and the process Ids change all the time. My understanding is that the query waits for a table lock but the lock is released after less than one second. Is this a normal/acceptable behaviour or could it be worth to do some fine tuning on the query cache, perhaps removing it completely?