Choosing the right tool for the job, a digest.

If your application is CPU-bound, Perl will certainly be quite a poor fit, and be beaten by C (obviously) and most of the time, Java.

If your application is IO-bound (many are, be it network or disk IO), most languages will perform about the same.

In your case, most naive perl implementations will be slower than Java, being CPU-bound. However, the win may be in the development and maintenance time; after all if your program runs in 30 ms instead of 5 ms, that hardly makes any difference to you.