In addition to what tchrist said, it's worth noting that the parsimonious matching can be much slower than other choices because of all the backtracking it has to do.

I don't know what your data looks like, but if you can make limits on the regex based on what you know about the data, then that will help. For instance, in the HTML comments you're capturing HINT followed by almost anything. Does it need to be that liberal? Or are you really only looking for HINT followed by some non-whitespace? If you can change the HINT.*? part of your regex to HINT\S* you will get much faster times.

Of course, that's just a guess on my part, but anything you can do to help the regex matcher limit its range of work, the better.

xoxo,
Andy

In reply to Re: Very slow regex substitution on Unicode string by petdance
in thread Very slow regex substitution on Unicode string by pbijnens

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.