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            <h2 class="title" style="clear: both"><a id="mempset_priority"></a>DbMpoolFile::set_priority()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;

int
DbMpoolFile::set_priority(DB_CACHE_PRIORITY priority); </pre>
      <p>
            Set the cache priority for pages referenced by the 
            <a class="link" href="memp.html" title="Chapter 9.  The DbMpoolFile Handle">DbMpoolFile</a>  handle.
    </p>
      <p>
         The priority of a page biases the replacement algorithm to be more or
         less likely to discard a page when space is needed in the cache.
         The bias is temporary, and pages will eventually be discarded if they
         are not referenced again.  The <code class="methodname">DbMpoolFile::set_priority()</code> method is
         only advisory, and does not guarantee pages will be treated in a
         specific way.
    </p>
      <p>
         To set the priority for the pages belonging to a particular database,
         call the <code class="methodname">DbMpoolFile::set_priority()</code> method using the 
         <a class="link" href="memp.html" title="Chapter 9.  The DbMpoolFile Handle">DbMpoolFile</a>  handle
         returned by the <a class="xref" href="dbget_mpf.html" title="Db::get_mpf()">Db::get_mpf()</a>  method.
    </p>
      <p>
         The <code class="methodname">DbMpoolFile::set_priority()</code> method configures a file in the
         cache, not only operations performed using the specified 
         <a class="link" href="memp.html" title="Chapter 9.  The DbMpoolFile Handle">DbMpoolFile</a>  handle.
    </p>
      <p>
         The <code class="methodname">DbMpoolFile::set_priority()</code> method may be called at any time
         during the life of the application.
    </p>
      <p>
         The <code class="methodname">DbMpoolFile::set_priority()</code> <span>
            
            <span>
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            </span>
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp9109384"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp9108736"></a>priority</h4>
              </div>
            </div>
          </div>
          <p>
                          The <span class="bold"><strong>priority</strong></span> parameter must be set to
                          one of the following values:
                     </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p>
                  <code class="literal">DB_PRIORITY_VERY_LOW</code>
            </p>
                <p>
                 The lowest priority: pages are the most likely to be discarded.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_PRIORITY_LOW</code>
            </p>
                <p>
                The next lowest priority.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_PRIORITY_DEFAULT</code>
            </p>
                <p>
                The default priority.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_PRIORITY_HIGH</code>
            </p>
                <p>
                The next highest priority.
            </p>
              </li>
              <li>
                <p>
                  <code class="literal">DB_PRIORITY_VERY_HIGH</code>
            </p>
                <p>
                 The highest priority: pages are the least likely to be discarded.
            </p>
              </li>
            </ul>
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                 <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>, <a class="link" href="memp.html" title="Chapter 9.  The DbMpoolFile Handle">DbMpoolFile</a> 
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                     <a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a> 
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