Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
The original problem stated the integers were held in files. It would probably be worthwhile for me to alter the benchmark to pull in integers from a file instead. But then I'm testing IO, not the algorithm.

Not really. You'd at least be testing the real-world scenario. And what you'd find is most likely that the IO so completely swamps everything else once you get into using a hash that further savings will be immaterial. If saving the 20 seconds that the hash costs is important, you could use IO::AIO to read in the data and insert it into the hash - if I read that module right, you should be able to be inserting and reading simultaneously, which now brings you solely to reading speed (whether local disk or over the network). I doubt it'll be important.

Basically, this is the definition of premature optimisation. You're micro-optimising something that will have no effect on the overall speed because you're ignoring the elephant in the algorithm: disk IO.

That and the payoff isn't that great even when you do make this optimisation. Dropping from the hash to the array is a huge savings for the cost involved. Dropping to XS is not as good because the development and debug time likely will completely dwarf the savings again :-) For the record, I expect using IO::AIO to be cheaper to implement than your XS version, give a negligibly better savings, and still not be worth it overall :-)

In reply to Re^3: "Just use a hash": An overworked mantra? by Tanktalus
in thread "Just use a hash": An overworked mantra? by davido

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

  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?

What's my password?
Create A New User
Domain Nodelet?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others studying the Monastery: (1)
As of 2023-05-31 23:36 GMT
Find Nodes?
    Voting Booth?

    No recent polls found