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  17         <p>Library Version 11.2.5.3</p>
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  21           <th colspan="3" align="center">DB_ENV-&gt;set_cache_max()</th>
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  25           <th width="60%" align="center">Chapter 8.
  26               The  DB_MPOOLFILE Handle
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  37             <h2 class="title" style="clear: both"><a id="envset_cache_max"></a>DB_ENV-&gt;set_cache_max()</h2>
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  41       <pre class="programlisting">#include &lt;db.h&gt;
  42
  43 int
  44 DB_ENV-&gt;set_cache_max(DB_ENV *dbenv, u_int32_t gbytes, u_int32_t bytes);  </pre>
  45       <p>
  46          Sets the maximum cache size in bytes. The specified size is
  47          rounded to the nearest multiple of the cache region size, which is
  48          the initial cache size divided by the number of regions specified
  49          to the <a class="xref" href="envset_cachesize.html" title="DB_ENV-&gt;set_cachesize()">DB_ENV-&gt;set_cachesize()</a> method.  If no value is
  50          specified, it defaults to the initial cache
  51          size.
  52     </p>
  53       <p>
  54          The database environment's maximum cache size may also be
  55          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
  56          the entry in that file is a single line with the string
  57          "set_cache_max", one or more whitespace characters, and the
  58          maximum cache size in bytes, specified in two parts: the gigabytes
  59          of cache and the additional bytes of cache. Because the
  60          <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,
  61          it will silently overrule configuration done before that time.
  62     </p>
  63       <p>
  64          The <code class="methodname">DB_ENV-&gt;set_cache_max()</code> method configures a database environment,
  65          not only operations performed using the specified
  66          <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
  67     </p>
  68       <p>
  69          The <code class="methodname">DB_ENV-&gt;set_cache_max()</code> method must be
  70          called prior to opening the database environment.
  71     </p>
  72       <p>
  73          The <code class="methodname">DB_ENV-&gt;set_cache_max()</code> <span>
  74             <span>
  75                   method returns a non-zero error value on failure and 0 on success.
  76             </span>
  77
  78         </span>
  79     </p>
  80       <div class="sect2" lang="en" xml:lang="en">
  81         <div class="titlepage">
  82           <div>
  83             <div>
  84               <h3 class="title"><a id="idp61280496"></a>Parameters</h3>
  85             </div>
  86           </div>
  87         </div>
  88         <div class="sect3" lang="en" xml:lang="en">
  89           <div class="titlepage">
  90             <div>
  91               <div>
  92                 <h4 class="title"><a id="idp61291016"></a>gbytes</h4>
  93               </div>
  94             </div>
  95           </div>
  96           <p>
  97                          The  <span class="bold"><strong>gbytes</strong></span> parameter specifies the number of
  98                          bytes which, when added to the <span class="bold"><strong>bytes</strong></span>
  99                          parameter,  specifies the maximum size of the cache.
 100                      </p>
 101         </div>
 102         <div class="sect3" lang="en" xml:lang="en">
 103           <div class="titlepage">
 104             <div>
 105               <div>
 106                 <h4 class="title"><a id="idp61277832"></a>bytes</h4>
 107               </div>
 108             </div>
 109           </div>
 110           <p>
 111                          The  <span class="bold"><strong>bytes</strong></span> parameter specifies the number of
 112                          bytes which, when added to the <span class="bold"><strong>gbytes</strong></span>
 113                          parameter,  specifies the maximum size of the cache.
 114                      </p>
 115         </div>
 116       </div>
 117       <div class="sect2" lang="en" xml:lang="en">
 118         <div class="titlepage">
 119           <div>
 120             <div>
 121               <h3 class="title"><a id="idp61281328"></a>Errors</h3>
 122             </div>
 123           </div>
 124         </div>
 125         <p>
 126                          The <code class="methodname">DB_ENV-&gt;set_cache_max()</code> <span>
 127             <span>
 128                  method may fail and return one of the following non-zero errors:
 129             </span>
 130
 131         </span>
 132                     </p>
 133         <div class="sect3" lang="en" xml:lang="en">
 134           <div class="titlepage">
 135             <div>
 136               <div>
 137                 <h4 class="title"><a id="idp61280280"></a>EINVAL</h4>
 138               </div>
 139             </div>
 140           </div>
 141           <p>
 142                 An invalid flag value or parameter was specified.
 143             </p>
 144         </div>
 145       </div>
 146       <div class="sect2" lang="en" xml:lang="en">
 147         <div class="titlepage">
 148           <div>
 149             <div>
 150               <h3 class="title"><a id="idp61302080"></a>Class</h3>
 151             </div>
 152           </div>
 153         </div>
 154         <p>
 155                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>
 156             </p>
 157       </div>
 158       <div class="sect2" lang="en" xml:lang="en">
 159         <div class="titlepage">
 160           <div>
 161             <div>
 162               <h3 class="title"><a id="idp61304208"></a>See Also</h3>
 163             </div>
 164           </div>
 165         </div>
 166         <p>
 167                      <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a>
 168                 </p>
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