Unless you use something somewhat exotic, your problem won't be about performance about an interpreted language A and compiled language B.

Because if you/your team know A and not B and so write way better code in A than B you can end up having much better performance in A than B. If you have people experienced in one language and the language/libraries can does the job you need, stick to it.

Here's a link about regex in various languages; you'll see that regex are implemented better in some language even if compiled or not: http://benchmarksgame.alioth.debian.org/u64q/performance.php?test=regexdna