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@@ -50,10 +50,8 @@
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<div class="section" id="frequently-asked-questions">
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<h1>Frequently Asked Questions<a class="headerlink" href="#frequently-asked-questions" title="Permalink to this headline">¶</a></h1>
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-<div class="section" id="questions">
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-<h2>Questions<a class="headerlink" href="#questions" title="Permalink to this headline">¶</a></h2>
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<div class="section" id="mysql-is-throwing-deadlock-errors-what-can-i-do">
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-<h3>MySQL is throwing deadlock errors, what can I do?<a class="headerlink" href="#mysql-is-throwing-deadlock-errors-what-can-i-do" title="Permalink to this headline">¶</a></h3>
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+<h2>MySQL is throwing deadlock errors, what can I do?<a class="headerlink" href="#mysql-is-throwing-deadlock-errors-what-can-i-do" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> MySQL has default isolation level set to <tt class="docutils literal"><span class="pre">REPEATABLE-READ</span></tt>,
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if you don’t really need that, set it to <tt class="docutils literal"><span class="pre">READ-COMMITTED</span></tt>.
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You can do that by adding the following to your <tt class="docutils literal"><span class="pre">my.cnf</span></tt>:</p>
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@@ -66,31 +64,31 @@ Transaction Model and Locking</a> in the MySQL user manual.</p>
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<p>(Thanks to Honza Kral and Anton Tsigularov for this solution)</p>
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</div>
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<div class="section" id="celeryd-is-not-doing-anything-just-hanging">
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-<h3>celeryd is not doing anything, just hanging<a class="headerlink" href="#celeryd-is-not-doing-anything-just-hanging" title="Permalink to this headline">¶</a></h3>
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+<h2>celeryd is not doing anything, just hanging<a class="headerlink" href="#celeryd-is-not-doing-anything-just-hanging" title="Permalink to this headline">¶</a></h2>
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<dl class="docutils">
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<dt><strong>Answer:</strong> See <a class="reference internal" href="#mysql-is-throwing-deadlock-errors-what-can-i-do">MySQL is throwing deadlock errors, what can I do?</a>.</dt>
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<dd>or <cite>Why is Task.delay/apply* just hanging?</cite>.</dd>
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</dl>
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</div>
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<div class="section" id="why-is-task-delay-apply-just-hanging">
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-<h3>Why is Task.delay/apply* just hanging?`<a class="headerlink" href="#why-is-task-delay-apply-just-hanging" title="Permalink to this headline">¶</a></h3>
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+<h2>Why is Task.delay/apply* just hanging?`<a class="headerlink" href="#why-is-task-delay-apply-just-hanging" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> <tt class="xref docutils literal"><span class="pre">amqplib</span></tt> hangs if it isn’t able to authenticate to the
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AMQP server, so make sure you are able to access the configured vhost using
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the user and password.</p>
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</div>
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<div class="section" id="why-won-t-celeryd-run-on-freebsd">
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-<h3>Why won’t celeryd run on FreeBSD?<a class="headerlink" href="#why-won-t-celeryd-run-on-freebsd" title="Permalink to this headline">¶</a></h3>
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+<h2>Why won’t celeryd run on FreeBSD?<a class="headerlink" href="#why-won-t-celeryd-run-on-freebsd" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> multiprocessing.Pool requires a working POSIX semaphore
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implementation which isn’t enabled in FreeBSD by default. You have to enable
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POSIX semaphores in the kernel and manually recompile multiprocessing.</p>
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</div>
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<div class="section" id="i-m-having-integrityerror-duplicate-key-errors-why">
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-<h3>I’m having <tt class="docutils literal"><span class="pre">IntegrityError:</span> <span class="pre">Duplicate</span> <span class="pre">Key</span></tt> errors. Why?<a class="headerlink" href="#i-m-having-integrityerror-duplicate-key-errors-why" title="Permalink to this headline">¶</a></h3>
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+<h2>I’m having <tt class="docutils literal"><span class="pre">IntegrityError:</span> <span class="pre">Duplicate</span> <span class="pre">Key</span></tt> errors. Why?<a class="headerlink" href="#i-m-having-integrityerror-duplicate-key-errors-why" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> See <a class="reference internal" href="#mysql-is-throwing-deadlock-errors-what-can-i-do">MySQL is throwing deadlock errors, what can I do?</a>.
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Thanks to howsthedotcom.</p>
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</div>
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<div class="section" id="why-won-t-my-task-run">
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-<h3>Why won’t my Task run?<a class="headerlink" href="#why-won-t-my-task-run" title="Permalink to this headline">¶</a></h3>
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+<h2>Why won’t my Task run?<a class="headerlink" href="#why-won-t-my-task-run" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> Did you register the task in the applications <tt class="docutils literal"><span class="pre">tasks.py</span></tt> module?
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(or in some other module Django loads by default, like <tt class="docutils literal"><span class="pre">models.py</span></tt>?).
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Also there might be syntax errors preventing the tasks module being imported.</p>
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@@ -104,11 +102,11 @@ task manually:</p>
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if it’s able to find the task, or if some other error is happening.</p>
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</div>
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<div class="section" id="why-won-t-my-periodic-task-run">
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-<h3>Why won’t my Periodic Task run?<a class="headerlink" href="#why-won-t-my-periodic-task-run" title="Permalink to this headline">¶</a></h3>
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+<h2>Why won’t my Periodic Task run?<a class="headerlink" href="#why-won-t-my-periodic-task-run" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> See <a class="reference internal" href="#why-won-t-my-task-run">Why won’t my Task run?</a>.</p>
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</div>
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<div class="section" id="how-do-i-discard-all-waiting-tasks">
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-<h3>How do I discard all waiting tasks?<a class="headerlink" href="#how-do-i-discard-all-waiting-tasks" title="Permalink to this headline">¶</a></h3>
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+<h2>How do I discard all waiting tasks?<a class="headerlink" href="#how-do-i-discard-all-waiting-tasks" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> Use <tt class="docutils literal"><span class="pre">celery.task.discard_all()</span></tt>, like this:</p>
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<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">celery.task</span> <span class="kn">import</span> <span class="n">discard_all</span>
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<span class="gp">>>> </span><span class="n">discard_all</span><span class="p">()</span>
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@@ -120,7 +118,7 @@ if it’s able to find the task, or if some other error is happening.</p>
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accomplish the same thing.</p>
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</div>
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<div class="section" id="i-ve-discarded-messages-but-there-are-still-messages-left-in-the-queue">
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-<h3>I’ve discarded messages, but there are still messages left in the queue?<a class="headerlink" href="#i-ve-discarded-messages-but-there-are-still-messages-left-in-the-queue" title="Permalink to this headline">¶</a></h3>
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+<h2>I’ve discarded messages, but there are still messages left in the queue?<a class="headerlink" href="#i-ve-discarded-messages-but-there-are-still-messages-left-in-the-queue" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> Tasks are acknowledged (removed from the queue) as soon
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as they are actually executed. After the worker has received a task, it will
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take some time until it is actually executed, especially if there are a lot
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@@ -133,7 +131,7 @@ waiting tasks you have to stop all the workers, and then discard the tasks
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using <tt class="docutils literal"><span class="pre">discard_all</span></tt>.</p>
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</div>
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<div class="section" id="can-i-use-celery-with-activemq-stomp">
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-<h3>Can I use celery with ActiveMQ/STOMP?<a class="headerlink" href="#can-i-use-celery-with-activemq-stomp" title="Permalink to this headline">¶</a></h3>
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+<h2>Can I use celery with ActiveMQ/STOMP?<a class="headerlink" href="#can-i-use-celery-with-activemq-stomp" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer</strong>: Yes. But this is somewhat experimental for now.
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It is certainly working ok for me in a test configuration, but it has not
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been tested in production like RabbitMQ. If you have any problems with
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@@ -186,7 +184,7 @@ the one with the most capabilities won).</p>
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specific options.</p>
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</div>
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<div class="section" id="which-features-are-not-supported-when-using-stomp">
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-<h3>Which features are not supported when using STOMP?<a class="headerlink" href="#which-features-are-not-supported-when-using-stomp" title="Permalink to this headline">¶</a></h3>
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+<h2>Which features are not supported when using STOMP?<a class="headerlink" href="#which-features-are-not-supported-when-using-stomp" title="Permalink to this headline">¶</a></h2>
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<p>This is a (possible incomplete) list of features not available when
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using the STOMP backend:</p>
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<ul class="simple">
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@@ -197,7 +195,7 @@ using the STOMP backend:</p>
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</ul>
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</div>
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<div class="section" id="can-i-send-some-tasks-to-only-some-servers">
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-<h3>Can I send some tasks to only some servers?<a class="headerlink" href="#can-i-send-some-tasks-to-only-some-servers" title="Permalink to this headline">¶</a></h3>
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+<h2>Can I send some tasks to only some servers?<a class="headerlink" href="#can-i-send-some-tasks-to-only-some-servers" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> As of now there is only one use-case that works like this,
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and that is tasks of type <tt class="docutils literal"><span class="pre">A</span></tt> can be sent to servers <tt class="docutils literal"><span class="pre">x</span></tt> and <tt class="docutils literal"><span class="pre">y</span></tt>,
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while tasks of type <tt class="docutils literal"><span class="pre">B</span></tt> can be sent to server <tt class="docutils literal"><span class="pre">z</span></tt>. One server can’t
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@@ -263,7 +261,7 @@ configuration:</p>
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</div>
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</div>
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<div class="section" id="can-i-use-celery-without-django">
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-<h3>Can I use celery without Django?<a class="headerlink" href="#can-i-use-celery-without-django" title="Permalink to this headline">¶</a></h3>
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+<h2>Can I use celery without Django?<a class="headerlink" href="#can-i-use-celery-without-django" title="Permalink to this headline">¶</a></h2>
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<p><strong>Answer:</strong> Yes.</p>
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<p>Celery uses something called loaders to read/setup configuration, import
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modules that registers tasks and to decide what happens when a task is
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@@ -333,7 +331,6 @@ run <tt class="docutils literal"><span class="pre">celeryinit</span></tt> to cre
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</pre></div>
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</div>
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</div>
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-</div>
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</div>
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@@ -345,7 +342,6 @@ run <tt class="docutils literal"><span class="pre">celeryinit</span></tt> to cre
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<h3><a href="index.html">Table Of Contents</a></h3>
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<ul>
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<li><a class="reference external" href="">Frequently Asked Questions</a><ul>
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-<li><a class="reference external" href="#questions">Questions</a><ul>
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<li><a class="reference external" href="#mysql-is-throwing-deadlock-errors-what-can-i-do">MySQL is throwing deadlock errors, what can I do?</a></li>
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<li><a class="reference external" href="#celeryd-is-not-doing-anything-just-hanging">celeryd is not doing anything, just hanging</a></li>
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<li><a class="reference external" href="#why-is-task-delay-apply-just-hanging">Why is Task.delay/apply* just hanging?`</a></li>
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@@ -361,8 +357,6 @@ run <tt class="docutils literal"><span class="pre">celeryinit</span></tt> to cre
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<li><a class="reference external" href="#can-i-use-celery-without-django">Can I use celery without Django?</a></li>
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</ul>
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</li>
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-</ul>
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-</li>
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</ul>
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<h4>Previous topic</h4>
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Ask Solem