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<h2 class="title" style="clear: both"><a id="memptrickle"></a>DbEnv::memp_trickle()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbEnv::memp_trickle(int percent, int *nwrotep);</pre>
<p>
The <code class="methodname">DbEnv::memp_trickle()</code> method ensures that a specified percent of
the pages in the cache are clean, by writing dirty pages
to their backing files.
</p>
<p>
The purpose of the <code class="methodname">DbEnv::memp_trickle()</code> function is to enable a
memory pool manager to ensure that a page is always available for
reading in new information without having to wait for a write.
</p>
<p>
The <code class="methodname">DbEnv::memp_trickle()</code> <span>
<span>
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.
</span>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp8725008"></a>Parameters</h3>
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<div class="sect3" lang="en" xml:lang="en">
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<div>
<h4 class="title"><a id="idp8743992"></a>percent</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>percent</strong></span> parameter is the percent
of the pages in the cache that should be clean.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp8774312"></a>nwrotep</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>nwrotep</strong></span> parameter references
memory into which the number of pages written to reach the specified
percentage is copied.
</p>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp8758008"></a>Errors</h3>
</div>
</div>
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<p>
The <code class="methodname">DbEnv::memp_trickle()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
</span>
following non-zero errors:
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp8780344"></a>EINVAL</h4>
</div>
</div>
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<p>
An invalid flag value or parameter was specified.
</p>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
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<h3 class="title"><a id="idp8778368"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>, <a class="link" href="memp.html" title="Chapter 9. The DbMpoolFile Handle">DbMpoolFile</a>
</p>
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<h3 class="title"><a id="idp8769752"></a>See Also</h3>
</div>
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<a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a>
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