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<h2 class="title" style="clear: both"><a id="envset_lk_max_lockers"></a>DbEnv::set_lk_max_lockers()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbEnv::set_lk_max_lockers(u_int32_t max); </pre>
<p>
Set the maximum number of locking entities supported by the Berkeley
DB environment. This value is used by
<a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> to estimate how
much space to allocate for various lock-table data structures. The
default value is 1000 lockers. For specific information on
configuring the size of the lock subsystem, see <a href="../../programmer_reference/lock_max.html" class="olink">Configuring locking: sizing the system</a>.
</p>
<p>
The database environment's maximum number of lockers 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_lk_max_lockers", one or more whitespace characters, and the
number of lockers. 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_lk_max_lockers()</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_lk_max_lockers()</code> method may not be called after the
<a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> method is
called. If the database environment already exists when
<a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> is called, the
information specified to <code class="methodname">DbEnv::set_lk_max_lockers()</code> will be
ignored.
</p>
<p>
The <code class="methodname">DbEnv::set_lk_max_lockers()</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>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="id1680267"></a>Parameters</h3>
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<h4 class="title"><a id="id1680350"></a>max</h4>
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<p>
The <span class="bold"><strong>max</strong></span> parameter is the maximum
number simultaneous locking entities supported by the Berkeley DB
environment.
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<h3 class="title"><a id="id1680443"></a>Errors</h3>
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</div>
</div>
<p>
The <code class="methodname">DbEnv::set_lk_max_lockers()</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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<h4 class="title"><a id="id1679942"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If the method was called after <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a>
was called; or if an invalid flag value or parameter was specified.
</p>
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</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h3 class="title"><a id="id1680376"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>,
<a class="link" href="lock.html" title="Chapter 7. The DbLock Handle">DbLock</a>
</p>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="id1680352"></a>See Also</h3>
</div>
</div>
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<p>
<a class="xref" href="lock.html#locklist" title="Locking Subsystem and Related Methods">Locking Subsystem and Related Methods</a>
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