http://www.perlmonks.org?node_id=110176

dws has asked for the wisdom of the Perl Monks concerning the following question:

I seek the wisdom of those with knowledge of The Source.

What overhead is incurred when a script reads from <DATA>?

Does the runtime actually open the script file and seek to a known (remembered) location? Or is some deeper optimization at work?

Is it any more or less expensive to put data after __DATA__ vs. storing it in a separate file? Are there advantages beyond convenience and the assumption that the script will still be in the kernel's disk cache?