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<h3>DbEnv::set_mp_max_write</h3>
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<h3><pre>
#include <db_cxx.h>
<p>
int
DbEnv::set_mp_max_write(int maxwrite, db_timeout_t maxwrite_sleep);
<p>
int
DbEnv::get_mp_max_write(int *maxwritep, db_timeout_t *maxwrite_sleepp);
</pre></h3>
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<h3>Description: DbEnv::set_mp_max_write</h3>
<p>The DbEnv::set_mp_max_write method limits the number of sequential write
operations scheduled by the library when flushing dirty pages from the
cache.</p>
<p>The DbEnv::set_mp_max_write 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.
</p>
<h3>Parameters</h3>
<dl compact>
<dt><b>maxwrite</b><dd>The maximum number of sequential write operations scheduled by the
library when flushing dirty pages from the cache, or 0 if there is
no limitation on the number of sequential write operations.
<dt><b>maxwrite_sleep</b><dd>The number of microseconds the thread of control should pause before
scheduling further write operations. It must be specified as an
unsigned 32-bit number of microseconds, limiting the maximum pause to
roughly 71 minutes.
</dl>
<h3>Errors</h3>
<p>The DbEnv::set_mp_max_write method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<dl compact>
<dt>EINVAL<dd>An
invalid flag value or parameter was specified.
</dl>
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<h3>Description: DbEnv::get_mp_max_write</h3>
<p>The DbEnv::get_mp_max_write method returns the current maximum number of
sequential write operations and microseconds to pause.</p>
<p>The DbEnv::get_mp_max_write method may be called at any time during the life of the
application.</p>
<p>The DbEnv::get_mp_max_write 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.
</p>
<h3>Parameters</h3>
<dl compact>
<dt><b>maxwritep</b><dd>The <b>maxwritep</b> parameter references memory into which
the maximum number of sequential write operations is copied.
<dt><b>maxwrite_sleepp</b><dd>The <b>maxwrite_sleepp</b> parameter references memory into which
the microseconds to pause before scheduling further write operations is copied.
</dl>
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<h3>Class</h3>
<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a>
<h3>See Also</h3>
<a href="../api_cxx/memp_list.html">Memory Pools and Related Methods</a>
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