Problem with kernel_mutex in MySQL 5.1 and MySQL 5.5 is known: Bug report. In fact in MySQL 5.6 there are some fixes that suppose to provide a solution, but MySQL 5.6 yet has long way ahead before production, and it is also not clear if the problem is really fixed.
Meantime the problem with kernel_mutex is raising, I had three customer problems related to performance drops during the last month.
So what can be done there ? Let’s run some benchmarks.
But some theory before benchmarks. InnoDB uses …[Read more...]