_(Prevalence) is a variation on the theme of _(Orthogonal Persistence) where the graph model of the computation universe is kept in memory, with atomic transactions to it being logged.

See _(Prevayler),
_(Advogato article|http://www.advogato.org/article/398.html),
_(Rebel with a cause|http://homepage.mac.com/svc/RebelWithACause/index.html),
etc.

<hr>

<span class="comment">
I don't understand why you guys are so impressed by this idea: it is a patch of some implementation techniques for <em>In-Memory</em> (even known as <em>Main-Memory</em>) _(DBMS) .. but pratically without the Management System. And that is a virtue to your eyes? Embarrassing! -- _(MaD70)
</span>

<ul class="links">
<li>_("ON PREVAYLING IGNORANCE"|http://www.dbdebunk.com/page/page/806810.htm)
<br>Excerpt:
<blockquote>
I got several emails the last few months on Prevayler. Lost cause. Suggest those with some brain should simply ignore it. -- Fabian Pascal
</blockquote>
<li>See this debate <em>In defense of Prevalence</em> on the Tunes general mailing list, _("2004-February Archives by Thread"|http://lists.tunes.org/archives/tunes/2004-February/thread.html).
</ul>
