Your sample data (provided elsewhere in this thread) reflects lines of approximately 390 bytes. Your filesize is 500MB. So you have over 1.3 million lines to process. On my system calling strftime "%M,%Y,%m,%d,%H,%j,%W,%u,%A", gmtime $Y
1.3 million times takes over 30 seconds.
If the first ten digits that comprise "$Y" are repeated many times, you could cache on that value and not have to make 1.3 million calls to gmtime, and 1.3 million calls to strftime. But you're still calling split 1.3 million times, substr 1.3 million times, and so on.
You may find it better to chunk the input file and process it with four workers, each writing its own output files. Then cat the output files together. It's possible (though not entirely certain) that with a sane number of workers each doing its share of the work this could go faster.
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||