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

int
DbEnv::set_cache_max(u_int32_t gbytes, u_int32_t bytes); </pre>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> method sets the maximum cache size, in
         bytes. The specified size is rounded to the nearest multiple of the
         cache region size, which is the initial cache size divided by the
         number of regions specified to the 
         <a class="xref" href="envset_cachesize.html" title="DbEnv::set_cachesize()">DbEnv::set_cachesize()</a> 
         method.  If no value is specified, it defaults to the initial cache
         size.
    </p>
      <p>
         The database environment's maximum cache size may also be configured using the
         environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.  The
         syntax of the entry in that file is a single line with the string "set_cache_max", one or
         more whitespace characters, and the size in bytes. Because the 
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the
         database environment is opened, it will silently overrule configuration done before that
         time.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> method configures a database environment,
         not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  handle.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</code> method may be called at any time during
         the life of the application.
    </p>
      <p>
         The <code class="methodname">DbEnv::set_cache_max()</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="id1692382"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
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            <div>
              <div>
                <h4 class="title"><a id="id1692544"></a>bytes</h4>
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          <p>
                         The  <span class="bold"><strong>bytes</strong></span> parameter specifies the number of
                         bytes which, when added to the <span class="bold"><strong>gbytes</strong></span>
                         parameter,  specifies the maximum size of the cache.
                     </p>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="id1692631"></a>gbytes</h4>
              </div>
            </div>
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          <p>
                         The  <span class="bold"><strong>gbytes</strong></span> parameter specifies the number of
                         bytes which, when added to the <span class="bold"><strong>bytes</strong></span>
                         parameter,  specifies the maximum size of the cache.
                     </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="id1692689"></a>Errors</h3>
            </div>
          </div>
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        <p>
                         The <code class="methodname">DbEnv::set_cache_max()</code> <span>
            
            <span>
                method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            </span>
        </span>
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="id1692691"></a>EINVAL</h4>
              </div>
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          <p>
                An invalid flag value or parameter was specified.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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          <div>
            <div>
              <h3 class="title"><a id="id1692603"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>  
            </p>
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              <h3 class="title"><a id="id1692576"></a>See Also</h3>
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        <p>
                     <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 
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