You need to profile your code. Going by how long print statements seem to take is about as useful as checking wind speed with a wetted finger. For a start, unless you have disabled output buffering, when you see output can be completely unrelated to when your program executed the print statement. In extreme cases, it could be displayed hours later.

The reason for the loops question is that the statement contains two fairly heavily indirected references. In high iteration count tight loops it can make sense to remove invarient parts of such statements from the loop through the use of temporary variables, but without profiling, random tuning is pointless.

It's like trying to improve the performance of your family saloon by polishing the paintwork, whilst ignoring the two hundred weight of junk in the boot and the roof rack.

Grab Devel::Smallprof which will quickly and easily allow you to see exactly where any perfomance bottleneck exist, on a line-by-line basis.

update: what BrowserUk said, especially the part about output buffering: print statements are not generally a reliable way to measure timing (though you could include the current millisecond time, as given by Time::Hires in your debugging line, which should give you a reasonable indication), but even then, the if(...) statement you posted should probably take a lot less time to execute than printing a line to stdout.

Print statements aren't an accurate way to measure performance. Try using Devel::SmallProf. It can be used from the command line like so perl -d:SmallProf your_script.pl. The output shows how often each line is executed and the amount of time it used.