Reply to Chen regarding Porting the Black Hole Solver to C

Shlomi Fish <shlomif-ik1l9ssToec+JF/[email protected]> Wed, 25 Aug 2010 13:10:24 +0300
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Hi all,

on Twitter I mentioned that I've started porting my Black Hole Solitaire 
solver from Perl to C and that it will hopefully make it faster:

http://twitter.com/shlomif/status/22027561541

Chen replied thusly:

http://twitter.com/gwenshap/status/22031112275

{{{
Why go to all the effort without knowing what causes your code to be slow and 
how C can help? Don't guess when you can measure!
}}}

So here is my reply: my code is not slow as Perl code goes, but it still often 
takes many seconds to solve a given deal of Black Hole Solitaire. As I'd like 
to run the solver on a range of deals in order to collect some statistics, I 
expect the Perl code to be too slow for that. The code is algorithmic and I'd 
expect that executing the bytecode by the Perl 5 backend to incur a large 
amount of overhead.

My code is very minimal as it is, and it's not very complicated or 
sophisticated so I expect a conversion to C to yield great speed (and possibly 
also memory consumption) benefits.

For more information see my:

* http://en.wikibooks.org/wiki/Optimizing_Code_for_Speed

I've replied to it here instead of on Twitter, because I didn't have enough 
character quota to express myself properly. (Also I thought it may be of 
interest to the list.).

Regards,

	Shlomi Fish

-- 
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      <p>Hi all,<br>
<br>
on Twitter I mentioned that I've started porting my Black Hole Solitaire <br>
solver from Perl to C and that it will hopefully make it faster:<br>
<br>
<a href="http://twitter.com/shlomif/status/22027561541">http://twitter.com/shlomif/status/22027561541</a><br>
<br>
Chen replied thusly:<br>
<br>
<a href="http://twitter.com/gwenshap/status/22031112275">http://twitter.com/gwenshap/status/22031112275</a><br>
<br>
{{{<br>
Why go to all the effort without knowing what causes your code to be slow and <br>
how C can help? Don't guess when you can measure!<br>
}}}<br>
<br>
So here is my reply: my code is not slow as Perl code goes, but it still often <br>
takes many seconds to solve a given deal of Black Hole Solitaire. As I'd like <br>
to run the solver on a range of deals in order to collect some statistics, I <br>
expect the Perl code to be too slow for that. The code is algorithmic and I'd <br>
expect that executing the bytecode by the Perl 5 backend to incur a large <br>
amount of overhead.<br>
<br>
My code is very minimal as it is, and it's not very complicated or <br>
sophisticated so I expect a conversion to C to yield great speed (and possibly <br>
also memory consumption) benefits.<br>
<br>
For more information see my:<br>
<br>
* <a href="http://en.wikibooks.org/wiki/Optimizing_Code_for_Speed">http://en.wikibooks.org/wiki/Optimizing_Code_for_Speed</a><br>
<br>
I've replied to it here instead of on Twitter, because I didn't have enough <br>
character quota to express myself properly. (Also I thought it may be of <br>
interest to the list.).<br>
<br>
Regards,<br>
<br>
	Shlomi Fish<br>
<br>
-- <br>
----------------------------------------------------------<br>
Shlomi Fish       <a href="http://www.shlomifish.org/">http://www.shlomifish.org/</a><br>
List of Portability Libraries - <a href="http://shlom.in/port-libs">http://shlom.in/port-libs</a><br>
<br>
God considered inflicting XSLT as the tenth plague of Egypt, but then<br>
decided against it because he thought it would be too evil.<br>
<br>
Please reply to list if it's a mailing list post - <a href="http://shlom.in/reply">http://shlom.in/reply</a> .<br>
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    padding: 0 0 0 8px;
  }

  #ygrp-text {
    font-family: Georgia;
  }

  #ygrp-text p {
    margin: 0 0 1em 0;
  }

  #ygrp-text tt {
    font-size: 120%;
  }

  #ygrp-vital ul li:last-child {
    border-right: none !important; 
  } 
  -->
  </style>
</head>

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</html>
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