Beefy Boxes and Bandwidth Generously Provided by pair Networks
The stupid question is the question not asked
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??
I think of it this way:
  • When the first PC's came along, you would try to keep as much in memory as possible because disk access was so very slow compared to the CPU. (I once rewrote a Clipper (Dbase3) program that took > 30 minutes in another language in which I could just use RAM, and it went to 15 seconds ;-).
  • Lately, CPU's have become much faster. So much faster that RAM (other than the CPU L1 and L2 caches) has become very slow compared to the CPU. So now you should be trying to keep everything in the CPU caches.
  • One way to achieve this is to not keep temporary values in memory, but calculate them again and again (as long as it stays in the L1 and L2 cache).
Probably not a technically correct view of what's happening, but a model that I'm working with. I'm open to anyone correcting this model.

Liz

P.S.: Yes, my background is experimental physics, sometime long ago.


In reply to Re: Re: Out-Of-Date Optimizations? New Idioms? RAM vs. CPU by liz
in thread Out-Of-Date Optimizations? New Idioms? RAM vs. CPU by liz

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!
  • 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, 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, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • Outside of code tags, you may need to use entities for some characters:
            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.
  • 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 wandering the Monastery: (6)
    As of 2014-09-01 18:56 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      My favorite cookbook is:










      Results (15 votes), past polls