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     <h4 class="title">
      <a name="channels-startup-options">
      </a>
      19.2.2.3 Startup Options and Replication Channels
     </h4>
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  <p>
   This section describes startup options which are impacted by the
      addition of replication channels.
  </p>
  <p>
   The following startup options now affect
   <span class="emphasis">
    <em>
     all
    </em>
   </span>
   channels in a replication topology.
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-binary-log.html#sysvar_log_replica_updates">
       <code class="literal">
        --log-replica-updates
       </code>
      </a>
     </p>
     <p>
      All transactions received by the replica (even from multiple
          sources) are written in the binary log.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-replica.html#sysvar_relay_log_purge">
       <code class="literal">
        --relay-log-purge
       </code>
      </a>
     </p>
     <p>
      When set, each channel purges its own relay log automatically.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-replica.html#sysvar_replica_transaction_retries">
       <code class="literal">
        --replica-transaction-retries
       </code>
      </a>
     </p>
     <p>
      The specified number of transaction retries can take place on
          all applier threads of all channels.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-replica.html#option_mysqld_skip-replica-start">
       <code class="option">
        --skip-replica-start
       </code>
      </a>
     </p>
     <p>
      No replication threads start on any channels.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-replica.html#sysvar_replica_skip_errors">
       <code class="literal">
        --replica-skip-errors
       </code>
      </a>
     </p>
     <p>
      Execution continues and errors are skipped for all channels.
     </p>
    </li>
   </ul>
  </div>
  <p>
   The values set for the following startup options apply on each
      channel; since these are
   <a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
    <span class="command">
     <strong>
      mysqld
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   startup
      options, they are applied on every channel.
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      <code class="option">
       --max-relay-log-size=
       <em class="replaceable">
        <code>
         size
        </code>
       </em>
      </code>
     </p>
     <p>
      Maximum size of the individual relay log file for each
          channel; after reaching this limit, the file is rotated.
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --relay-log-space-limit=
       <em class="replaceable">
        <code>
         size
        </code>
       </em>
      </code>
     </p>
     <p>
      Upper limit for the total size of all relay logs combined, for
          each individual channel. For
      <em class="replaceable">
       <code>
        N
       </code>
      </em>
      channels, the combined size of these logs is limited to
      <a class="link" href="replication-options-replica.html#sysvar_relay_log_space_limit">
       <code class="literal">
        relay_log_space_limit *
        <em class="replaceable">
         <code>
          N
         </code>
        </em>
       </code>
      </a>
      .
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --replica-parallel-workers=
       <em class="replaceable">
        <code>
         value
        </code>
       </em>
      </code>
     </p>
     <p>
      Number of replication applier threads per channel.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a class="link" href="replication-options-replica.html#sysvar_replica_checkpoint_group">
       <code class="literal">
        replica_checkpoint_group
       </code>
      </a>
     </p>
     <p>
      Waiting time by an receiver thread for each source.
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --relay-log-index=filename
      </code>
     </p>
     <p>
      Base name for each channel's relay log index file. See
      <a class="xref" href="channels-naming-conventions.html" title="19.2.2.4 Replication Channel Naming Conventions">
       Section 19.2.2.4, “Replication Channel Naming Conventions”
      </a>
      .
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --relay-log=filename
      </code>
     </p>
     <p>
      Denotes the base name of each channel's relay log file.
          See
      <a class="xref" href="channels-naming-conventions.html" title="19.2.2.4 Replication Channel Naming Conventions">
       Section 19.2.2.4, “Replication Channel Naming Conventions”
      </a>
      .
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --replica-net-timeout=
       <em class="replaceable">
        <code>
         N
        </code>
       </em>
      </code>
     </p>
     <p>
      This value is set per channel, so that each channel waits for
      <em class="replaceable">
       <code>
        N
       </code>
      </em>
      seconds to check for a broken
          connection.
     </p>
    </li>
    <li class="listitem">
     <p>
      <code class="option">
       --replica-skip-counter=
       <em class="replaceable">
        <code>
         N
        </code>
       </em>
      </code>
     </p>
     <p>
      This value is set per channel, so that each channel skips
      <em class="replaceable">
       <code>
        N
       </code>
      </em>
      events from its source.
     </p>
    </li>
   </ul>
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