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Related papers: PTHash: Revisiting FCH Minimal Perfect Hashing

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Consistent Hashing functions are widely used for load balancing across a variety of applications. However, the original presentation and typical implementations of Consistent Hashing rely on randomised allocation of hash codes to keys which…

Data Structures and Algorithms · Computer Science 2015-03-19 Matthew Sackman

A minimal perfect hash function (MPHF) maps a set $S$ of $n$ keys to the first $n$ integers without collisions. There is a lower bound of $n\log_2e-O(\log n)$ bits of space needed to represent an MPHF. A matching upper bound is obtained…

Data Structures and Algorithms · Computer Science 2023-11-14 Hans-Peter Lehmann , Peter Sanders , Stefan Walzer

Hashing has been widely used for efficient similarity search based on its query and storage efficiency. To obtain better precision, most studies focus on designing different objective functions with different constraints or penalty terms…

Data Structures and Algorithms · Computer Science 2018-10-02 Xingbo Liu , Xiushan Nie , Yilong Yin

Similarity searches are a critical task in data mining. As data sets grow larger, exact nearest neighbor searches quickly become unfeasible, leading to the adoption of approximate nearest neighbor (ANN) searches. ANN has been studied for…

Information Retrieval · Computer Science 2025-11-21 Alima Subedi , Sankalpa Pokharel , Satish Puri

Hashing is a basic tool for dimensionality reduction employed in several aspects of machine learning. However, the perfomance analysis is often carried out under the abstract assumption that a truly random unit cost hash function is used,…

Machine Learning · Statistics 2017-11-27 Søren Dahlgaard , Mathias Bæk Tejs Knudsen , Mikkel Thorup

In a recent paper from SODA11 \cite{kminwise} the authors introduced a general framework for exponential time improvement of \minwise based algorithms by defining and constructing almost \kmin independent family of hash functions. Here we…

Data Structures and Algorithms · Computer Science 2011-02-18 Guy Feigenblat , Ely Porat , Ariel Shiftan

The retrieval problem is the problem of associating data with keys in a set. Formally, the data structure must store a function f: U ->{0,1}^r that has specified values on the elements of a given set S, a subset of U, |S|=n, but may have…

Data Structures and Algorithms · Computer Science 2008-03-27 Martin Dietzfelbinger , Rasmus Pagh

We introduce PaCHash, a hash table that stores its objects contiguously in an array without intervening space, even if the objects have variable size. In particular, each object can be compressed using standard compression techniques. A…

Data Structures and Algorithms · Computer Science 2022-11-09 Florian Kurpicz , Hans-Peter Lehmann , Peter Sanders

Locality-sensitive hashing (LSH) is an effective randomized technique widely used in many machine learning tasks. The cost of hashing is proportional to data dimensions, and thus often the performance bottleneck when dimensionality is high…

Machine Learning · Computer Science 2023-09-28 Zongyuan Tan , Hongya Wang , Bo Xu , Minjie Luo , Ming Du

Consistent hashing (CH) is a central building block in many networking applications, from datacenter load-balancing to distributed storage. Unfortunately, state-of-the-art CH solutions cannot ensure full consistency under arbitrary changes…

Data Structures and Algorithms · Computer Science 2020-11-24 Gal Mendelson , Shay Vargaftik , Katherine Barabash , Dean Lorenz , Isaac Keslassy , Ariel Orda

The monotone minimal perfect hash function (MMPHF) problem is the following indexing problem. Given a set $S= \{s_1,\ldots,s_n\}$ of $n$ distinct keys from a universe $U$ of size $u$, create a data structure $DS$ that answers the following…

Data Structures and Algorithms · Computer Science 2022-07-26 Sepehr Assadi , Martin Farach-Colton , William Kuszmaul

The construction of perfect hash functions is a well-studied topic. In this paper, this concept is generalized with the following definition. We say that a family of functions from $[n]$ to $[k]$ is a $\delta$-balanced $(n,k)$-family of…

Data Structures and Algorithms · Computer Science 2008-12-18 Noga Alon , Shai Gutner

Keyword-based search in text-rich multi-dimensional datasets facilitates many novel applications and tools. In this paper, we consider objects that are tagged with keywords and are embedded in a vector space. For these datasets, we study…

Databases · Computer Science 2014-09-16 Vishwakarma Singh , Ambuj K. Singh

This work focuses on representing very high-dimensional global image descriptors using very compact 64-1024 bit binary hashes for instance retrieval. We propose DeepHash: a hashing scheme based on deep networks. Key to making DeepHash work…

Computer Vision and Pattern Recognition · Computer Science 2016-02-17 Jie Lin , Olivier Morere , Vijay Chandrasekhar , Antoine Veillard , Hanlin Goh

Hash functions are cryptographic tools, which are notably involved in integrity checking and password storage. They are of primary importance to improve the security of exchanges through the Internet. However, as security flaws have been…

Cryptography and Security · Computer Science 2016-08-23 Jacques M. Bahi , Jean-François Couchot , Christophe Guyeux

Consistent hashing (CH) has been pivotal as a data router and load balancer in diverse fields, including distributed databases, cloud infrastructure, and peer-to-peer networks. However, existing CH algorithms often fall short in…

Data Structures and Algorithms · Computer Science 2023-11-21 Chao Dong , Fang Wang , Dan Feng

Hash tables are ubiquitous, and the choice of hash function, which maps a key to a bucket, is key to their performance. We argue that the predominant approach of fixing the hash function for the lifetime of the hash table is suboptimal and…

Data Structures and Algorithms · Computer Science 2026-02-09 Gábor Melis

Consistent hashing is a technique for distributing data across a network of nodes in a way that minimizes reorganization when nodes join or leave the network. It is extensively applied in modern distributed systems as a fundamental…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-03-18 Massimo Coluzzi , Amos Brocco , Alessandro Antonucci , Tiziano Leidi

Random hashing can provide guarantees regarding the performance of data structures such as hash tables---even in an adversarial setting. Many existing families of hash functions are universal: given two data objects, the probability that…

Data Structures and Algorithms · Computer Science 2018-10-16 Dmytro Ivanchykhin , Sergey Ignatchenko , Daniel Lemire

The field of Automatic Machine Learning (AutoML) has recently attained impressive results, including the discovery of state-of-the-art machine learning solutions, such as neural image classifiers. This is often done by applying an…