<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>Database Limits and Portability</title> <link rel="stylesheet" href="gettingStarted.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Getting Started with Berkeley DB" /> <link rel="up" href="introduction.html" title="Chapter 1. Introduction to Berkeley DB" /> <link rel="prev" href="accessmethods.html" title="Access Methods" /> <link rel="next" href="coreExceptions.html" title="Exception Handling" /> </head> <body> <div xmlns="" class="navheader"> <div class="libver"> <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">Database Limits and Portability</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="accessmethods.html">Prev</a> </td> <th width="60%" align="center">Chapter 1. Introduction to Berkeley DB </th> <td width="20%" align="right"> <a accesskey="n" href="coreExceptions.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="databaseLimits"></a>Database Limits and Portability</h2> </div> </div> </div> <p> Berkeley DB provides support for managing everything from very small databases that fit entirely in memory, to extremely large databases holding millions of records and terabytes of data. An individual DB database can store up to 256 terabytes of data. By using multiple databases, it is possible to use DB to store and manage petabytes of information. Within a single database, individual record keys or record data can be used to store up to 4 gigabytes of data. </p> <p> DB's databases store data in a binary format that is portable across platforms, even of differing endian-ness. Be aware, however, that portability aside, some performance issues can crop up in the event that you are using little endian architecture. See <a class="xref" href="btree.html#comparators" title="Setting Comparison Functions">Setting Comparison Functions</a> for more information. </p> <p> Also, DB's databases and data structures are designed for concurrent access — they are thread-safe, and they share well across multiple processes. That said, in order to allow multiple processes to share databases and the cache, DB makes use of mechanisms that do not work well on network-shared drives (NFS or Windows networks shares, for example). For this reason, you cannot place your DB databases and environments on network-mounted drives. </p> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="accessmethods.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="introduction.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="coreExceptions.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">Access Methods </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> Exception Handling</td> </tr> </table> </div> </body> </html>