Sindbad~EG File Manager
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<p>
The largest database file that Berkeley DB can handle
depends on the page size selected by the application. Berkeley
DB stores database file page numbers as unsigned 32-bit
numbers and database file page sizes as unsigned 16-bit
numbers. Using the maximum database page size of 65536, this
results in a maximum database file size of
2<sup>48</sup> (256 terabytes). The
minimum database page size is 512 bytes, which results in a
minimum maximum database size of
2<sup>41</sup> (2 terabytes).
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In order to store petabytes of data you can use
multiple database files.
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The largest database file Berkeley DB can support is
potentially further limited if the host system does not have
filesystem support for files larger than
2<sup>32</sup>, including the ability to
seek to absolute offsets within those files.
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<p>
The largest key or data item that Berkeley DB can support
is 2<sup>32</sup>, or more likely limited by
available memory. Specifically, while key and data byte
strings may be of essentially unlimited length, any one of
them must fit into available memory so that it can be returned
to the application. As some of the Berkeley DB interfaces
return both key and data items to the application, those
interfaces will require that any key/data pair fit
simultaneously into memory. Further, as the access methods may
need to compare key and data items with other key and data
items, it may be a requirement that any two key or two data
items fit into available memory. Finally, when writing
applications supporting transactions, it may be necessary to
have an additional copy of any data item in memory for logging
purposes.
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The maximum Btree depth is 255.
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Sindbad File Manager Version 1.0, Coded By Sindbad EG ~ The Terrorists