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<title>Berkeley DB: Db.set_cache_priority</title>
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<h1>Db.set_cache_priority</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void set_cache_priority(int priority)
throws DbException;
</pre></h3>
<h1>Description</h1>
<p>Set the cache priority for pages from the specified database. The
priority of a page biases the replacement algorithm to be more or less
likely to discard a page when space is needed in the buffer pool. The
bias is temporary, and pages will eventually be discarded if they are
not referenced again. The Db.set_cache_priority interface is
only advisory, and does not guarantee pages will be treated in a specific
way.
<p>The <b>priority</b> argument must be set to one of the following values:
<p><dl compact>
<p><dt><a name="Db.DB_PRIORITY_VERY_LOW">Db.DB_PRIORITY_VERY_LOW</a><dd>The lowest priority: pages are the most likely to be discarded.
<dt><a name="Db.DB_PRIORITY_LOW">Db.DB_PRIORITY_LOW</a><dd>The next lowest priority.
<dt><a name="Db.DB_PRIORITY_DEFAULT">Db.DB_PRIORITY_DEFAULT</a><dd>The default priority.
<dt><a name="Db.DB_PRIORITY_HIGH">Db.DB_PRIORITY_HIGH</a><dd>The next highest priority.
<dt><a name="Db.DB_PRIORITY_VERY_HIGH">Db.DB_PRIORITY_VERY_HIGH</a><dd>The highest priority: pages are the least likely to be discarded.
</dl>
<p>The Db.set_cache_priority method configures a database, not only operations performed
using the specified <a href="../api_java/db_class.html">Db</a> handle.
<p>The Db.set_cache_priority interface may be called at any time during the life of
the application.
<p>The Db.set_cache_priority method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The Db.set_cache_priority method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the Db.set_cache_priority method may fail and
throw a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_java/db_class.html">Db</a>
<h1>See Also</h1>
<a href="../api_java/db_list.html">Databases and Related Methods</a>
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