If you're worried about speed, I don't see any way that the argument passing mechanism could be your bottleneck -- if you want to trim clock cycles, start your search elsewhere. However, if you're sure argument passing is really slowing you down, then whatever sub you're calling probably shouldn't be in a sub. If it must be in a sub, consider either using lexical variables bound by a closure (no arguments "passed"), or passing references to the large objects.

Anyway, I will attempt to answer your question. You should look at the Benchmark module comes with your Perl distribution. I ran a few test cases, and found the shift method faster for very small arguments (ints, small strings, references), and the @_ method faster for passing larger objects (strings). Try it out yourself with whatever data is most common in your app.

blokhead