Beefy Boxes and Bandwidth Generously Provided by pair Networks
Welcome to the Monastery
 
PerlMonks  

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
Sure. Algorithms can matter. But, they only do so now when dealing with large datasets

But "large" depends strongly on the algorithm.

I remember reading a node here (can't find it, sorry) about a regex taking exponential time matching some piece of HTML.

For an algorithm that needs exponential time a line of 80 chars can be long. Really. In 10 years that limit might be 100. Or 120.

Typical examples are the knapsack problem that appear in real world applications over and over again, which takes exponential time when solved with brute force. Approximation algorithms can solve it much faster, even if a bit inaccurate.

I'm sure even you would argue that you should optimize when a O(2**n) code hits you.

But if you normally don't optimize, you have no feeling for what is slow and what isn't, don't know about profiling etc. Which is why I do optimize my applications from time to time.

BTW a real world project that has been hit by missing optimizations recently is the KindaPerl6 compiler, which was so slow during bootstrap that it just wasn't practicable anymore. It took the fun out of the development process, and now I haven't seen a single kp6 commit since... lemme check... 2008-03-16. (Surely this wasn't the only problem, but IMHO it was the one with largest impact).


In reply to Re^3: CPU cycles DO NOT MATTER! by moritz
in thread CPU cycles DO NOT MATTER! by dragonchild

Title:
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 or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

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

How do I use this? | Other CB clients
Other Users?
Others surveying the Monastery: (7)
As of 2021-06-17 09:41 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    What does the "s" stand for in "perls"? (Whence perls)












    Results (83 votes). Check out past polls.

    Notices?