lbcd/database/internal/treap/README.md
Dave Collins b580cdb7d3 database: Replace with new version.
This commit removes the old database package, moves the new package into
its place, and updates all imports accordingly.
2016-04-12 14:55:15 -05:00

2.3 KiB

treap

[Build Status] (https://travis-ci.org/btcsuite/btcd)

Package treap implements a treap data structure that is used to hold ordered key/value pairs using a combination of binary search tree and heap semantics. It is a self-organizing and randomized data structure that doesn't require complex operations to to maintain balance. Search, insert, and delete operations are all O(log n). Both mutable and immutable variants are provided.

The mutable variant is typically faster since it is able to simply update the treap when modifications are made. However, a mutable treap is not safe for concurrent access without careful use of locking by the caller and care must be taken when iterating since it can change out from under the iterator.

The immutable variant works by creating a new version of the treap for all mutations by replacing modified nodes with new nodes that have updated values while sharing all unmodified nodes with the previous version. This is extremely useful in concurrent applications since the caller only has to atomically replace the treap pointer with the newly returned version after performing any mutations. All readers can simply use their existing pointer as a snapshot since the treap it points to is immutable. This effectively provides O(1) snapshot capability with efficient memory usage characteristics since the old nodes only remain allocated until there are no longer any references to them.

Package treap is licensed under the copyfree ISC license.

Usage

This package is only used internally in the database code and as such is not available for use outside of it.

Documentation

[GoDoc] (http://godoc.org/github.com/btcsuite/btcd/database/internal/treap)

Full go doc style documentation for the project can be viewed online without installing this package by using the GoDoc site here: http://godoc.org/github.com/btcsuite/btcd/database/internal/treap

You can also view the documentation locally once the package is installed with the godoc tool by running godoc -http=":6060" and pointing your browser to http://localhost:6060/pkg/github.com/btcsuite/btcd/database/internal/treap

License

Package treap is licensed under the copyfree ISC License.