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<h2 class="title" style="clear: both"><a id="envset_mp_mtxcount"></a>DbEnv::set_mp_mtxcount()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbEnv::set_mp_mtxcount(u_int32_t mtxcount);</pre>
<p>
The <code class="methodname">DbEnv::set_mp_mtxcount()</code> method
overrides the default number of mutexes for the hash table in each
memory pool cache. The defualt is one mutex per hash bucket.
Setting it to a lower number decreases the number of mutexes used
and the amount of memory needed to store them at the expense of
concurrency in the memory pool. This can also improve startup
time. Setting a number greater than the number size of the hash
table will waste mutexes and space.
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You must call this method only before the environment is opened.
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Specifies the number of mutexes allocated to the buffer
pool hash table.
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<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>,
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<a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a>,
<a class="xref" href="envget_mp_mtxcount.html" title="DbEnv::get_mp_mtxcount()">DbEnv::get_mp_mtxcount()</a>
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