Sindbad~EG File Manager
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<p>Library Version 18.1.40</p>
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<h2 class="title" style="clear: both"><a id="new_flags"></a>New Replication Manager Flags</h2>
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<p>
Prior to the 18.1 release, Berkeley DB's replication manager managed connections
using the <code class="literal">select()</code> call which has a limitation of 1024 open
file descriptors. Application working with a very large number of databases, files
or network connections and thus consuming more than 1024 file descriptors, were
likely to run into this limitation.
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<p>
Berkeley DB's 18.1 release offers the use of <code class="literal">poll()</code>
and/or <code class="literal">epoll()</code> in preference to <code class="literal">select()</code>.
In the new implementation, <code class="literal">poll()</code> is preferred over
<code class="literal">select()</code> because it does not limit the number of open file
descriptors. If <code class="literal">epoll()</code> is available and the number of
open file descriptors is greater than 1024, <code class="literal">epoll()</code> is
preferred over <code class="literal">poll()</code> because it scales better.
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No changes are necessary to use the new defaults, but new flags have been added
for the user to disable <code class="literal">poll()</code> and <code class="literal">epoll()</code> and
fall back to <code class="literal">select()</code>.
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<code class="literal">DB_REPMGR_CONF_DISABLE_POLL</code>
<p>
A new <code class="literal">flags</code> parameter value for the
<code class="literal">DB_ENV->rep_set_config()</code>
method to indicate that <code class="literal">poll()</code> should not be used.
</p>
</li>
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<code class="literal">DB_REPMGR_CONF_DISABLE_EPOLL</code>
<p>
A new <code class="literal">flags</code> parameter value for the
<code class="literal">DB_ENV->rep_set_config()</code> method to
indicate that <code class="literal">epoll()</code> should be used (if supported
by the target OS). Note that this flag needs to be explicitly
specified for <code class="literal">epoll()</code> to be used by the replication
subsystem.
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Sindbad File Manager Version 1.0, Coded By Sindbad EG ~ The Terrorists