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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_mp_max_write()</th>
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  23         <tr>
  24           <td width="20%" align="left"><a accesskey="p" href="mempset_mp_max_openfd.html">Prev</a> </td>
  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="mempset_mp_max_write"></a>DB_ENV-&gt;set_mp_max_write()</h2>
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  41       <pre class="programlisting">#include &lt;db.h&gt;
  42
  43 int
  44 DB_ENV-&gt;set_mp_max_write(DB_ENV *env, int maxwrite,
  45                          db_timeout_t maxwrite_sleep); </pre>
  46       <p>
  47          The <code class="methodname">DB_ENV-&gt;set_mp_max_write()</code> method limits the number of sequential
  48          write operations scheduled by the library when flushing dirty pages
  49          from the cache.
  50     </p>
  51       <p>
  52          The database environment's maximum number of sequential write
  53          operations may also be configured using the environment's
  54          <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
  55          line with the string "set_mp_max_write", one or more whitespace
  56          characters, and the maximum number of sequential writes and the
  57          number of microseconds to sleep, also separated by whitespace
  58          characters. 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
  59          environment is opened, it will silently overrule configuration
  60          done before that time.
  61     </p>
  62       <p>
  63          The <code class="methodname">DB_ENV-&gt;set_mp_max_write()</code> method configures a database
  64          environment, not only operations performed using the specified
  65          <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
  66     </p>
  67       <p>
  68          The <code class="methodname">DB_ENV-&gt;set_mp_max_write()</code> <span>
  69             <span>
  70                   method returns a non-zero error value on failure and 0 on success.
  71             </span>
  72
  73         </span>
  74     </p>
  75       <div class="sect2" lang="en" xml:lang="en">
  76         <div class="titlepage">
  77           <div>
  78             <div>
  79               <h3 class="title"><a id="idp61335456"></a>Parameters</h3>
  80             </div>
  81           </div>
  82         </div>
  83         <div class="sect3" lang="en" xml:lang="en">
  84           <div class="titlepage">
  85             <div>
  86               <div>
  87                 <h4 class="title"><a id="idp61335928"></a>maxwrite</h4>
  88               </div>
  89             </div>
  90           </div>
  91           <p>
  92                           The maximum number of sequential write operations scheduled by the
  93                           library when flushing dirty pages from the cache, or 0 if there is no
  94                           limitation on the number of sequential write operations.
  95                      </p>
  96         </div>
  97         <div class="sect3" lang="en" xml:lang="en">
  98           <div class="titlepage">
  99             <div>
 100               <div>
 101                 <h4 class="title"><a id="idp61345424"></a>maxwrite_sleep</h4>
 102               </div>
 103             </div>
 104           </div>
 105           <p>
 106                           The number of microseconds the thread of control should pause before
 107                           scheduling further write operations.  It must be specified as an
 108                           unsigned 32-bit number of microseconds, limiting the maximum pause to
 109                           roughly 71 minutes.
 110                      </p>
 111         </div>
 112       </div>
 113       <div class="sect2" lang="en" xml:lang="en">
 114         <div class="titlepage">
 115           <div>
 116             <div>
 117               <h3 class="title"><a id="idp61336096"></a>Errors</h3>
 118             </div>
 119           </div>
 120         </div>
 121         <p>
 122                          The <code class="methodname">DB_ENV-&gt;set_mp_max_write()</code> <span>
 123             <span>
 124                  method may fail and return one of the following non-zero errors:
 125             </span>
 126
 127         </span>
 128                     </p>
 129         <div class="sect3" lang="en" xml:lang="en">
 130           <div class="titlepage">
 131             <div>
 132               <div>
 133                 <h4 class="title"><a id="idp61327296"></a>EINVAL</h4>
 134               </div>
 135             </div>
 136           </div>
 137           <p>
 138                 An invalid flag value or parameter was specified.
 139             </p>
 140         </div>
 141       </div>
 142       <div class="sect2" lang="en" xml:lang="en">
 143         <div class="titlepage">
 144           <div>
 145             <div>
 146               <h3 class="title"><a id="idp61325208"></a>Class</h3>
 147             </div>
 148           </div>
 149         </div>
 150         <p>
 151                  <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>, <a class="link" href="memp.html" title="Chapter 8.  The DB_MPOOLFILE Handle">DB_MPOOLFILE</a>
 152             </p>
 153       </div>
 154       <div class="sect2" lang="en" xml:lang="en">
 155         <div class="titlepage">
 156           <div>
 157             <div>
 158               <h3 class="title"><a id="idp61339248"></a>See Also</h3>
 159             </div>
 160           </div>
 161         </div>
 162         <p>
 163                      <a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a>
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