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13<b>DbEnv::memp_trickle</b>
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21<b><pre>
22#include &lt;db_cxx.h&gt;
23<p>
24int
25DbEnv::memp_trickle(int percent, int *nwrotep);
26</pre></b>
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28<b>Description: DbEnv::memp_trickle</b>
29<p>The DbEnv::memp_trickle method ensures that a specified percent of the pages
30in the shared memory pool are clean, by writing dirty pages to their
31backing files.</p>
32<p>The purpose of the DbEnv::memp_trickle function is to enable a memory
33pool manager to ensure that a page is always available for reading in new
34information without having to wait for a write.</p>
35<p>The DbEnv::memp_trickle method
36either returns a non-zero error value
37or throws an exception that encapsulates a non-zero error value on
38failure, and returns 0 on success.
39</p>
40<b>Parameters</b> <br>
41 <b>nwrotep</b><ul compact><li>The <b>nwrotep</b> parameter references memory into which
42 the number of pages written to reach the specified
43percentage is copied.</ul> 
44 <b>percent</b><ul compact><li>The <b>percent</b> parameter is the percent of the pages in the cache
45that should be clean.</ul>
46<br>
47<br><b>Errors</b>
48<p>The DbEnv::memp_trickle method
49may fail and throw
50<a href="../api_cxx/except_class.html">DbException</a>,
51encapsulating one of the following non-zero errors, or return one of
52the following non-zero errors:</p>
53<br>
54<b>EINVAL</b><ul compact><li>An
55invalid flag value or parameter was specified.</ul>
56<br>
57<hr size=1 noshade>
58<br><b>Class</b>
59<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a>
60<br><b>See Also</b>
61<a href="../api_cxx/memp_list.html">Memory Pools and Related Methods</a>
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