An obvious performance problem is that you keep on accessing $hash->$key. Perl has to do the work of a hash lookup every time. Insert my $value = $hash->$key; and access $value repeatedly instead.

Another small speedup. Don't use keys to dump data into an array that only exists for you to run through it. Just run directly through the array.

If you can figure out how to push both the data and this work to a decent relational database, you will see bigger speedups still.

Moving to a faster machine always helps. If your code is I/O bound and you can parallelize it, then that can speed things up. The same happens if you are CPU bound and have multiple CPUs or computers to take advantage of.

But at 0.0008 seconds per record, if it takes over 60 seconds, then you have over 75,000 records. At some point you have to understand that computers are not magic. Doing work takes time. You aren't going to hit a particular performance level just because the powers that be said that you must.

In reply to Re: Re: Need to process a tab delimted file *FAST* by tilly
in thread Need to process a tab delimted file *FAST* by devnul

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.