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Found 33 papers, 30 papers with code
Validating UTF-8 In Less Than One Instruction Per Byte
The majority of text is stored in UTF-8, which must be validated on ingestion.
Databases
Xor Filters: Faster and Smaller Than Bloom and Cuckoo Filters
We find that xor filters can be faster than Bloom and cuckoo filters while using less memory.
Data Structures and Algorithms
Parsing Gigabytes of JSON per Second
We are thus motivated to make JSON parsing as fast as possible.
Databases Performance
Faster Remainder by Direct Computation: Applications to Compilers and Software Libraries
Currently, the remainder of the division by a constant is computed from the quotient by a multiplication and a subtraction.
Mathematical Software Performance
Fast Random Integer Generation in an Interval
We review an unbiased function to generate ranged integers from a source of random words that avoids integer divisions with high probability.
Data Structures and Algorithms
Apache Calcite: A Foundational Framework for Optimized Query Processing Over Heterogeneous Data Sources
Apache Calcite is a foundational software framework that provides query processing, optimization, and query language support to many popular open-source data processing systems such as Apache Hive, Apache Storm, Apache Flink, Druid, and MapD.
Databases
Stream VByte: Faster Byte-Oriented Integer Compression
To surpass varint-G8IU, we present Stream VByte, a novel byte-oriented compression technique that separates the control stream from the encoded data.
Roaring Bitmaps: Implementation of an Optimized Software Library
Compressed bitmap indexes are used in systems such as Git or Oracle to accelerate queries.
Databases
Faster Base64 Encoding and Decoding Using AVX2 Instructions
Web developers use base64 formats to include images, fonts, sounds and other resources directly inside HTML, JavaScript, JSON and XML files.
Mathematical Software
Faster Population Counts Using AVX2 Instructions
Most processors have dedicated instructions to count the number of ones in a word (e. g., popcnt on x64 processors).
Data Structures and Algorithms
Upscaledb: Efficient Integer-Key Compression in a Key-Value Store using SIMD Instructions
In particular, a differentially coded SIMD binary-packing techniques (BP128) can offer a superior query speed (e. g., 40% better than an uncompressed database) while providing the best compression (e. g., by a factor of ten).
Databases
Regular and almost universal hashing: an efficient implementation
Many existing families of hash functions are universal: given two data objects, the probability that they have the same hash value is low given that we pick hash functions at random.
Data Structures and Algorithms Cryptography and Security
Consistently faster and smaller compressed bitmaps with Roaring
To better handle these cases, we build a new Roaring hybrid that combines uncompressed bitmaps, packed arrays and RLE compressed segments.
Databases
Faster 64-bit universal hashing using carry-less multiplications
Intel and AMD support the Carry-less Multiplication (CLMUL) instruction set in their x64 processors.
Data Structures and Algorithms Performance
Vectorized VByte Decoding
We consider the ubiquitous technique of VByte compression, which represents each integer as a variable length sequence of bytes.
A General SIMD-based Approach to Accelerating Compression Algorithms
Compression algorithms are important for data oriented tasks, especially in the era of Big Data.
Measuring academic influence: Not all citations are equal
Unlike the conventional h-index, it weights citations by how many times a reference is mentioned.
Bloofi: Multidimensional Bloom Filters
This problem cannot be solved by just constructing a Bloom filter on the union of all the sets.
Databases Data Structures and Algorithms
Better bitmap performance with Roaring bitmaps
On synthetic and real data, we find that Roaring bitmaps (1) often compress significantly better (e. g., 2 times) and (2) are faster than the compressed alternatives (up to 900 times faster for intersections).
Databases
Compressed bitmap indexes: beyond unions and intersections
Compressed bitmap indexes are used to speed up simple aggregate queries in databases.
Databases Data Structures and Algorithms
SIMD Compression and the Intersection of Sorted Integers
We can use the SIMD instructions available in common processors to boost the speed of integer compression schemes.
Information Retrieval Databases Performance
Decoding billions of integers per second through vectorization
In many important applications -- such as search engines and relational database systems -- data is stored in the form of arrays of integers.
Reordering Rows for Better Compression: Beyond the Lexicographic Order
For minimizing the number of runs in a run-length encoding compression scheme, the best approaches to row-ordering are derived from traveling salesman heuristics, although there is a significant trade-off between running time and compression.
Databases H.4.0
Strongly universal string hashing is fast
Our tests include hash functions designed for processors with the Carry-Less Multiplication (CLMUL) instruction set.
Databases Data Structures and Algorithms
The universality of iterated hashing over variable-length strings
Iterated hash functions process strings recursively, one character at a time.
Databases Data Structures and Algorithms
Reordering Columns for Smaller Indexes
Column-oriented indexes-such as projection or bitmap indexes-are compressed by run-length encoding to reduce storage and increase speed.
Databases
Sorting improves word-aligned bitmap indexes
Bitmap indexes must be compressed to reduce input/output costs and minimize CPU usage.
Databases
Faster Retrieval with a Two-Pass Dynamic-Time-Warping Lower Bound
We find that LB Improved-based search is faster.
Removing Manually-Generated Boilerplate from Electronic Texts: Experiments with Project Gutenberg e-Books
We investigate the case of the Project Gutenberg corpus, where most documents are in ASCII format with preambles and epilogues that are often copied and pasted or manually typed.
Recursive n-gram hashing is pairwise independent, at best
We prove that recursive hash families cannot be more than pairwise independent.
Slope One Predictors for Online Rating-Based Collaborative Filtering
Rating-based collaborative filtering is the process of predicting how a user would rate a given item from other user ratings.
Streaming Maximum-Minimum Filter Using No More than Three Comparisons per Element
The running maximum-minimum (max-min) filter computes the maxima and minima over running windows of size w. This filter has numerous applications in signal processing and time series analysis.
Data Structures and Algorithms F.2.1
A Better Alternative to Piecewise Linear Time Series Segmentation
We propose an adaptive time series model where the polynomial degree of each interval vary (constant, linear and so on).
