CL benchmarking

Is there a free benchmarking library for Common Lisp? Something like Haskell's Criterion, perhaps?

Alright, perhaps some of you lispers already know some of the answers.

1) I've read that keyword args are slower than common args. Is this true? How much do they slow down function calls? What about optional args?

2) What's the approximate cost of CLOS method dispatch? For instance: if one adds up a million boxed pairs of flonums, how much slower is it going to be if addition is defined as a generic, compared to using primitive addition?