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diff --git a/bdb/docs/ref/mp/config.html b/bdb/docs/ref/mp/config.html deleted file mode 100644 index cf311516de3..00000000000 --- a/bdb/docs/ref/mp/config.html +++ /dev/null @@ -1,55 +0,0 @@ -<!--$Id: config.so,v 10.17 2000/10/03 17:17:35 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Configuring the memory pool</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> - <a name="2"><!--meow--></a> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Memory Pool Subsystem</dl></h3></td> -<td width="1%"><a href="../../ref/mp/intro.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/txn/intro.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Configuring the memory pool</h1> -<p>There are two interfaces used for configuring the memory pool. -<p>The most important tuning parameter for almost all applications, including -Berkeley DB applications, is the size of the pool. There are two ways to -specify the pool size. First, calling the <a href="../../api_c/env_set_cachesize.html">DBENV->set_cachesize</a> function -specifies the pool size for all of the applications sharing the Berkeley DB -environment. Second, by calling the <a href="../../api_c/db_set_cachesize.html">DB->set_cachesize</a> function. The -latter only specifies a pool size for the specific database. Note, it is -meaningless to call <a href="../../api_c/db_set_cachesize.html">DB->set_cachesize</a> for a database opened inside -of a Berkeley DB environment, since the environment pool size will override any -pool size specified for a single database. For information on tuning the -Berkeley DB cache size, see <a href="../../ref/am_conf/cachesize.html">Selecting -a cache size</a>. -<p>The second memory pool configuration interface specifies the maximum size -of backing files to map into the process address space instead of copying -pages through the local cache. Only read-only database files can be -mapped into process memory. Because of the requirements of the Berkeley DB -transactional implementation, log records describing database changes must -be written to disk before the actual database changes. As mapping -read-write database files into process memory would permit the underlying -operating system to write modified database changes at will, it is not -supported. -<p>Mapping files into the process address space can result in -better-than-usual performance, as available virtual memory is normally -much larger than the local cache, and page faults are faster than page -copying on many systems. However, in the presence of limited virtual -memory it can cause resource starvation, and in the presence of large -databases, it can result in immense process sizes. -<p>To specify that no files are to be mapped into the process address space, -specify the <a href="../../api_c/env_open.html#DB_NOMMAP">DB_NOMMAP</a> flag to the <a href="../../api_c/env_set_flags.html">DBENV->set_flags</a> interface. -To specify that any individual file should not be mapped into the process -address space, specify the <a href="../../api_c/env_open.html#DB_NOMMAP">DB_NOMMAP</a> flag to the -<a href="../../api_c/memp_fopen.html">memp_fopen</a> interface. To limit the size of files mapped into the -process address space, use the <a href="../../api_c/env_set_mp_mmapsize.html">DBENV->set_mp_mmapsize</a> function. -<table><tr><td><br></td><td width="1%"><a href="../../ref/mp/intro.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/txn/intro.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |