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diff --git a/.html/mysql/broken-xa.html b/.html/mysql/broken-xa.html deleted file mode 100644 index b9a3568..0000000 --- a/.html/mysql/broken-xa.html +++ /dev/null @@ -1,115 +0,0 @@ -<!DOCTYPE html> -<html> -<head> - <title> - The Codex » - MySQL's Two-Phase Commit Implementation Is Broken - </title> - - <link - rel='stylesheet' - type='text/css' - href='http://fonts.googleapis.com/css?family=Buenard:400,700&subset=latin,latin-ext'> - <link - rel="stylesheet" - type="text/css" - href="../media/css/reset.css"> - <link - rel="stylesheet" - type="text/css" - href="../media/css/grimoire.css"> -</head> -<body> - -<div id="shell"> - - <ol id="breadcrumbs"> - - <li class="crumb-0 not-last"> - - <a href="../">index</a> - - </li> - - <li class="crumb-1 not-last"> - - <a href="./">mysql</a> - - </li> - - <li class="crumb-2 last"> - - broken-xa - - </li> - - </ol> - - - - <div id="article"> - <h1 id="mysqls-two-phase-commit-implementation-is-broken">MySQL's Two-Phase Commit Implementation Is Broken</h1> -<p>From <a href="http://dev.mysql.com/doc/refman/5.5/en/xa-restrictions.html">the fine -manual</a>:</p> -<blockquote> -<p>If an XA transaction has reached the PREPARED state and the MySQL server is -killed (for example, with kill -9 on Unix) or shuts down abnormally, the -transaction can be continued after the server restarts. However, if the -client reconnects and commits the transaction, the transaction will be -absent from the binary log even though it has been committed. This means the -data and the binary log have gone out of synchrony. An implication is that -<strong>XA cannot be used safely together with replication</strong>.</p> -</blockquote> -<p>(Emphasis mine.)</p> -<p>If you're solving the kinds of problems where two-phase commit and XA -transaction management look attractive, then you very likely have the kinds of -uptime requirements that make replication mandatory. “It works, but not with -replication” is effectively “it doesn't work.”</p> -<blockquote> -<p>It is possible that the server will roll back a pending XA transaction, even -one that has reached the PREPARED state. This happens if a client connection -terminates and the server continues to run, or if clients are connected and -the server shuts down gracefully.</p> -</blockquote> -<p>XA transaction managers assume that if every resource successfully reaches the -PREPARED state, then every resource will be able to commit the transaction -“eventually.” Resources that unilaterally roll back PREPARED transactions -violate this assumption pretty badly.</p> - </div> - - - -<div id="comments"> -<div id="disqus_thread"></div> -<script type="text/javascript"> - /* * * CONFIGURATION VARIABLES: EDIT BEFORE PASTING INTO YOUR WEBPAGE * * */ - var disqus_shortname = 'grimoire'; // required: replace example with your forum shortname - - /* * * DON'T EDIT BELOW THIS LINE * * */ - (function() { - var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true; - dsq.src = 'http://' + disqus_shortname + '.disqus.com/embed.js'; - (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq); - })(); -</script> -<noscript>Please enable JavaScript to view the <a href="http://disqus.com/?ref_noscript">comments powered by Disqus.</a></noscript> -<a href="http://disqus.com" class="dsq-brlink">comments powered by <span class="logo-disqus">Disqus</span></a> -</div> - - - - <div id="footer"> - <p> - - The Codex — - - Powered by <a href="http://markdoc.org/">Markdoc</a>. - -<a href="https://bitbucket.org/ojacobson/grimoire.ca/src/master/wiki/mysql/broken-xa.md">See this page on Bitbucket</a> (<a href="https://bitbucket.org/ojacobson/grimoire.ca/history-node/master/wiki/mysql/broken-xa.md">history</a>). - - </p> - </div> - -</div> -</body> -</html>
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