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<b>DB_ENV->set_lk_max_lockers</b>
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<b><pre>
#include <db.h>
<p>
int
DB_ENV->set_lk_max_lockers(DB_ENV *dbenv, u_int32_t max);
<p>
int
DB_ENV->get_lk_max_lockers(DB_ENV *dbenv, u_int32_t *lk_maxp);
</pre></b>
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<b>Description: DB_ENV->set_lk_max_lockers</b>
<p>Set the maximum number of locking entities supported by the Berkeley DB
environment. This value is used by <a href="../api_c/env_open.html">DB_ENV->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="../ref/lock/max.html">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="../ref/env/db_config.html#DB_CONFIG">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="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is read when the database environment
is opened, it will silently overrule configuration done before that
time.</p>
<p>The DB_ENV->set_lk_max_lockers method configures a database environment, not only operations
performed using the specified <a href="../api_c/env_class.html">DB_ENV</a> handle.</p>
<p>The DB_ENV->set_lk_max_lockers method may not be called after the <a href="../api_c/env_open.html">DB_ENV->open</a> method is
called.
If the database environment already exists when
<a href="../api_c/env_open.html">DB_ENV->open</a> is called, the information specified to DB_ENV->set_lk_max_lockers
will be ignored.
</p>
<p>The DB_ENV->set_lk_max_lockers method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
<b>max</b><ul compact><li>The <b>max</b> parameter is the maximum number simultaneous locking
entities supported by the Berkeley DB environment.</ul>
<br>
<br><b>Errors</b>
<p>The DB_ENV->set_lk_max_lockers method
may fail and return one of the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If the method was called after <a href="../api_c/env_open.html">DB_ENV->open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
<br>
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<b>Description: DB_ENV->get_lk_max_lockers</b>
<p>The DB_ENV->get_lk_max_lockers method returns the maximum number of lockers.</p>
<p>The DB_ENV->get_lk_max_lockers method may be called at any time during the life of the
application.</p>
<p>The DB_ENV->get_lk_max_lockers method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
<b>lk_maxp</b><ul compact><li>The DB_ENV->get_lk_max_lockers method returns the
maximum number of lockers in <b>lk_maxp</b>.</ul>
<br>
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<br><b>Class</b>
<a href="../api_c/env_class.html">DB_ENV</a>, <a href="../api_c/lock_class.html">DB_LOCK</a>
<br><b>See Also</b>
<a href="../api_c/lock_list.html">Locking Subsystem and Related Methods</a>
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