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DbEnv::set_lk_max_lockers
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#include &lt;db_cxx.h&gt;

int
DbEnv::set_lk_max_lockers(u_int32_t max);

int
DbEnv::get_lk_max_lockers(u_int32_t *, lk_maxp);
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Description: DbEnv::set_lk_max_lockers
Set the maximum number of locking entities supported by the Berkeley DB
environment. This value is used by <a href="../../db4-devel-4.7.25/api_cxx/env_open.html">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="../../db4-devel-4.7.25/ref/lock/max.html">Configuring locking: sizing the system</a>.
The database environment's maximum number of lockers may also be configured using the
environment's <a href="../../db4-devel-4.7.25/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="../../db4-devel-4.7.25/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.
The DbEnv::set_lk_max_lockers method configures a database environment, not only operations
performed using the specified <a href="../../db4-devel-4.7.25/api_cxx/env_class.html">DbEnv</a> handle.
The DbEnv::set_lk_max_lockers method may not be called after the <a href="../../db4-devel-4.7.25/api_cxx/env_open.html">DbEnv::open</a> method is
called.
If the database environment already exists when
<a href="../../db4-devel-4.7.25/api_cxx/env_open.html">DbEnv::open</a> is called, the information specified to DbEnv::set_lk_max_lockers
will be ignored.

The DbEnv::set_lk_max_lockers 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.

Parameters 
 max<ul compact><li>The max parameter is the maximum number simultaneous locking
entities supported by the Berkeley DB environment.</ul>
 
 Errors
The DbEnv::set_lk_max_lockers method
may fail and throw
<a href="../../db4-devel-4.7.25/api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:
 
EINVAL<ul compact><li>If the method was called after <a href="../../db4-devel-4.7.25/api_cxx/env_open.html">DbEnv::open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
 
<hr size=1 noshade>
Description: DbEnv::get_lk_max_lockers
The DbEnv::get_lk_max_lockers method returns the maximum number of lockers.
The DbEnv::get_lk_max_lockers method may be called at any time during the life of the
application.
The DbEnv::get_lk_max_lockers 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.

Parameters 
 lk_maxp<ul compact><li>The DbEnv::get_lk_max_lockers method returns the
maximum number of lockers in lk_maxp.</ul>
 
<hr size=1 noshade>
 Class
<a href="../../db4-devel-4.7.25/api_cxx/env_class.html">DbEnv</a>, <a href="../../db4-devel-4.7.25/api_cxx/lock_class.html">DbLock</a>
 See Also
<a href="../../db4-devel-4.7.25/api_cxx/lock_list.html">Locking Subsystem and Related Methods</a>
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