mirror of
https://git.FreeBSD.org/ports.git
synced 2024-12-15 03:14:23 +00:00
25 lines
1.2 KiB
Plaintext
25 lines
1.2 KiB
Plaintext
cdb is a fast, reliable, lightweight package for creating and reading
|
|
constant databases. Its database structure provides several features:
|
|
|
|
* Fast lookups: A successful lookup in a large database normally takes
|
|
just two disk accesses. An unsuccessful lookup takes only one.
|
|
* Low overhead: A database uses 2048 bytes, plus 24 bytes per record,
|
|
plus the space for keys and data.
|
|
* No random limits: cdb can handle any database up to 4 gigabytes. There
|
|
are no other restrictions; records don't even have to fit into memory.
|
|
Databases are stored in a machine-independent format.
|
|
* Fast atomic database replacement: cdbmake can rewrite an entire
|
|
database two orders of magnitude faster than other hashing packages.
|
|
* Fast database dumps: cdbdump prints the contents of a database in
|
|
cdbmake-compatible format.
|
|
|
|
cdb is designed to be used in mission-critical applications like e-mail.
|
|
Database replacement is safe against system crashes. Readers don't have
|
|
to pause during a rewrite.
|
|
|
|
Note for developers: packages that need to read cdb files should
|
|
incorporate the necessary portions of the cdb library rather than
|
|
relying on an external cdb library. (See WWW)
|
|
|
|
WWW: http://cr.yp.to/cdb.html
|