How to use Binary Search Trees part2(Data Structures and Algorithms)
1. Persistent Non-Blocking Binary Search Trees Supporting Wait-Free Range Queries(arXiv)
Author : Panagiota Fatourou, Eric Ruppert
Abstract : This paper presents the first implementation of a search tree data structure in an asynchronous shared-memory system that provides a wait-free algorithm for executing range queries on the tree, in addition to non-blocking algorithms for Insert, Delete and Find, using single-word Compare-and-Swap (CAS). The implementation is linearizable and tolerates any number of crash failures. Insert and Delete operations that operate on different parts of the tree run fully in parallel (without any interference with one another). We employ a lightweight helping mechanism, where each Insert, Delete and Find operation helps only update operations that affect the local neighbourhood of the leaf it arrives at. Similarly, a Scan helps only those updates taking place on nodes of the part of the tree it traverses, and therefore Scans operating on different parts of the tree do not interfere with one another. Our implementation works in a dynamic system where the number of processes may change over time. The implementation builds upon the non-blocking binary search tree implementation presented by Ellen et al. (in PODC 2010) by applying a simple mechanism to make the tree persistent
2. Random Binary Trees for Approximate Nearest Neighbour Search in Binary Space(arXiv)
Author : Michal Komorowski, Tomasz Trzcinski
Abstract : Approximate nearest neighbour (ANN) search is one of the most important problems in computer science fields such as data mining or computer vision. In this paper, we focus on ANN for high-dimensional binary vectors and we propose a simple yet powerful search method that uses Random Binary Search Trees (RBST). We apply our method to a dataset of 1.25M binary local feature descriptors obtained from a real-life image-based localisation system provided by Google as a part of Project Tango. An extensive evaluation of our method against the state-of-the-art variations of Locality Sensitive Hashing (LSH), namely Uniform LSH and Multi-probe LSH, shows the superiority of our method in terms of retrieval precision with performance boost of over 20%
3. A Concurrency-Optimal Binary Search Tree(arXiv)
Author : Vitaly Aksenov, Vincent Gramoli, Petr Kuznetsov, Anna Malova, Srivatsan Ravi
Abstract : The paper presents the first \emph{concurrency-optimal} implementation of a binary search tree (BST). The implementation, based on a standard sequential implementation of an internal tree, ensures that every \emph{schedule} is accepted, i.e., interleaving of steps of the sequential code, unless linearizability is violated. To ensure this property, we use a novel read-write locking scheme that protects tree \emph{edges} in addition to nodes. Our implementation outperforms the state-of-the art BSTs on most basic workloads, which suggests that optimizing the set of accepted schedules of the sequential code can be an adequate design principle for efficient concurrent data structures.
