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93 lines
4.1 KiB
HTML
93 lines
4.1 KiB
HTML
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>Managing Blocking Operations</title>
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<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Getting Started with Replicated Berkeley DB Applications" />
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<link rel="up" href="addfeatures.html" title="Chapter 5. Additional Features" />
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<link rel="prev" href="addfeatures.html" title="Chapter 5. Additional Features" />
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<link rel="next" href="autoinit.html" title="Stop Auto-Initialization" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 11.2.5.2</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">Managing Blocking Operations</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="addfeatures.html">Prev</a> </td>
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<th width="60%" align="center">Chapter 5. Additional Features</th>
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<td width="20%" align="right"> <a accesskey="n" href="autoinit.html">Next</a></td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="manageblock"></a>Managing Blocking Operations</h2>
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</div>
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</div>
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</div>
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<p>
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When a replica is in the process of synchronizing with
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its master, DB operations are blocked at some
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points during this process until the synchronization is
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completed. For replicas with a heavy read load, these
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blocked operations may represent an unacceptable loss
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in throughput.
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</p>
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<p>
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You can configure DB so that it will not block when synchronization is in
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process. Instead, the DB operation will fail,
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<span>
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immediately returning a <code class="literal">DB_REP_LOCKOUT</code> error.
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</span>
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When this happens, it is up to your application to determine
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what action to take (that is, logging the event, making an appropriate user
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response, retrying the operation, and so forth).
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</p>
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<p>
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To turn off blocking on synchronization, specify
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<span>
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<code class="literal">DB_REP_CONF_NOWAIT</code> to
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<code class="methodname">DbEnv::rep_set_config()</code>
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and then specify <code class="literal">1</code> to the <code class="literal">onoff</code>
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parameter. (Specify <code class="literal">0</code> to turn the feature off.)
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</span>
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</p>
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</div>
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<div class="navfooter">
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<hr />
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<table width="100%" summary="Navigation footer">
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<tr>
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<td width="40%" align="left"><a accesskey="p" href="addfeatures.html">Prev</a> </td>
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<td width="20%" align="center">
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<a accesskey="u" href="addfeatures.html">Up</a>
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</td>
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<td width="40%" align="right"> <a accesskey="n" href="autoinit.html">Next</a></td>
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</tr>
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<tr>
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<td width="40%" align="left" valign="top">Chapter 5. Additional Features </td>
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<td width="20%" align="center">
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<a accesskey="h" href="index.html">Home</a>
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</td>
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<td width="40%" align="right" valign="top"> Stop Auto-Initialization</td>
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</tr>
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</table>
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</div>
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</body>
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</html>
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