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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<div class="sect1" lang="en" xml:lang="en">
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<h2 class="title" style="clear: both"><a id="envset_cache_max"></a>DB_ENV->set_cache_max()</h2>
</div>
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</div>
<pre class="programlisting">#include <db.h>
int
DB_ENV->set_cache_max(DB_ENV *dbenv, u_int32_t gbytes, u_int32_t bytes); </pre>
<p>
Sets the maximum cache size in bytes. The specified size is
rounded to the nearest multiple of the cache region size, which is
the initial cache size divided by the number of regions specified
to the <a class="xref" href="envset_cachesize.html" title="DB_ENV->set_cachesize()">DB_ENV->set_cachesize()</a> method. If no value is
specified, it defaults to the initial cache
size.
</p>
<p>
The database environment's maximum cache size may also be configured using the
environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The
syntax of the entry in that file is a single line with the string "set_cache_max", one or
more whitespace characters, and the maximum cache size in bytes,
specified in two parts: the gigabytes of cache and the additional bytes of cache. Because the
<a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the
database environment is opened, it will silently overrule configuration done before that
time.
</p>
<p>
The <code class="methodname">DB_ENV->set_cache_max()</code> method configures a database environment,
not only operations performed using the specified
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handle.
</p>
<p>
The <code class="methodname">DB_ENV->set_cache_max()</code> method may be called at any time during
the life of the application.
</p>
<p>
The <code class="methodname">DB_ENV->set_cache_max()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp53149168"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp53156288"></a>gbytes</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>gbytes</strong></span> parameter specifies the number of
bytes which, when added to the <span class="bold"><strong>bytes</strong></span>
parameter, specifies the maximum size of the cache.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp53141376"></a>bytes</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>bytes</strong></span> parameter specifies the number of
bytes which, when added to the <span class="bold"><strong>gbytes</strong></span>
parameter, specifies the maximum size of the cache.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp53152928"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV->set_cache_max()</code> <span>
<span>
method may fail and return one of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp53156032"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
An invalid flag value or parameter was specified.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp53166944"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp53170248"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a>
</p>
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