FAD.js: Fast JSON Data Access Using JIT-based Speculative Optimizations

JSON is one of the most popular data encoding formats, with wide adoption in Databases and BigData frameworks, and native support in popular programming languages such as JavaScript/Node.js, Python, and R. Nevertheless, JSON data manipulation can easily become a performance bottleneck in modern language runtimes due to parsing and object materialization overheads. In this pa- per, we introduce Fad.js, a runtime system for fast manipulation of JSON objects in data-intensive applications. Fad.js is based on speculative just-in-time compilation and on direct access to raw data. Experiments show that applications using Fad.js can achieve speedups up to 2.7x for encoding and 9.9x for decoding JSON data when compared to state-of-the art JSON manipulation libraries.