how do I get consistent benchmark times with innodb buffer pool?

[Richard Pereira]

The environment I work in is extremely frustrating in that I have little to no control over my testing and production environments, and they are not identical!!

I have at least one query that runs fine on staging (or at least appears to), but seems to take up to 16 times longer in production (18.375 seconds compared to 4 minutes 49 seconds). Something is NOT RIGHT!!
These times appear to be without buffering/cache in place because second runs of the query in each environment are less than 1 second.

How can I get accurate times? I attempted SQL_NO_CACHE, but that doesn't help because, as I understand it, the INNODB buffer pool is not affected by that.

I need to be able to present some solid data, and not being able to get consistent run times, and not being sure buffering is or is not in play on either server makes this impossible.