It matters if you can optimise the I/O from disk.

Why? They are only read or written from disk once or a few times per run. Runs last many hours, or days. They are decoded many millions of times. The two are unrelated.

The values are compressed because there are many millions of them, and the 25% space saving is crucial both on disk and in memory. They are kept compressed whilst in memory because otherwise they would need to be paged to disk far more often.

The drift is that performance should rarely be addressed too specifically.

Hm. So you'd optimise IO performance but not decode performance?

This is a crock. I bet you'd be the first to complain if the p5p guys couldn't be bothered to consider the performance of the code they write.

I know my application's requirements, and with potentially, 2^47 states to explore, performance is crucial.

If you can't be bothered to make effective use of your users time, money and hardware by writing efficient code; why bother responding to a question clearly aimed at improving performance?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^4: unpacking 6-bit values by BrowserUk
in thread unpacking 6-bit values by BrowserUk

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.