Configure the total number of mutexes to allocate.
</p>
<p>
Berkeley DB allocates a default number of mutexes based on the initial
configuration of the database environment. That default calculation
may be too small if the application has an unusual need for mutexes
(for example, if the application opens an unexpectedly large number of
databases) or too large (if the application is trying to minimize its
memory footprint). The <codeclass="methodname">DB_ENV->mutex_set_max()</code> method is used to
specify an absolute number of mutexes to allocate.
</p>
<p>
Calling the <codeclass="methodname">DB_ENV->mutex_set_max()</code> method discards any value
previously set using the <codeclass="methodname">DB_ENV->mutex_set_increment()</code> method.
</p>
<p>
The database environment's total number of mutexes may also be
configured using the environment's <ahref="../../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
"mutex_set_max", one or more whitespace characters, and the total
number of mutexes. Because the <ahref="../../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 <codeclass="methodname">DB_ENV->mutex_set_max()</code> method configures a database environment,
not only operations performed using the specified <aclass="link"href="env.html"title="Chapter5. The DB_ENV Handle">DB_ENV</a> handle.
</p>
<p>
The <codeclass="methodname">DB_ENV->mutex_set_max()</code> method may not be called after the
<aclass="xref"href="envopen.html"title="DB_ENV->open()">DB_ENV->open()</a> method is called.
If the database environment already exists when
<aclass="xref"href="envopen.html"title="DB_ENV->open()">DB_ENV->open()</a> is called, the
information specified to <codeclass="methodname">DB_ENV->mutex_set_max()</code> will be ignored.
</p>
<p>
The <codeclass="methodname">DB_ENV->mutex_set_max()</code><span>
<span>
method returns a non-zero error value on failure and 0 on success.
