The very easiest way you could do this would be to divide your input file into N pieces and process each piece in parallel by starting your script on that piece. Have each process output to a file of its own and stitch them together at the end. If you start one process per CPU and the black-magic you do is CPU bound you could get something like a linear speedup.

That of course means you can't take data strictly from STDIN, but really that's a silly way to process 4.1GB of data!

If you really, really need to read it from a stream and output it in-order then you'll have to have a parent reading the stream, forking kids and then collecting the results in buffers so you can output in-order. Start with Parallel::ForkManager, which will handle giving out the work and then mix in some IO::Pipe and IO::Select for collecting the results. Be sure you divide the work into sizable chunks, forking a new child for each line isn't going to help very much!

Now go give it a try and don't come back until you have some code to post!

-sam

In reply to Re: How do you parallelize STDIN for large file processing? by samtregar
in thread How do you parallelize STDIN for large file processing? by forsaken75

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • 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:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, 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, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.