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<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.
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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>
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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.
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