Rapidgzip: Parallel Decompression and Seeking in Gzip Files Using Cache Prefetching

Research output: Contribution to book/conference proceedings/anthology/reportConference contributionContributedpeer-review


Gzip is a file compression format, which is ubiquitously used. Although a multitude of gzip implementations exist, only pugz can fully utilize current multi-core processor architectures for decompression. Yet, pugz cannot decompress arbitrary gzip files. It requires the decompressed stream to only contain byte values 9-126. In this work, we present a generalization of the parallelization scheme used by pugz that can be reliably applied to arbitrary gzip-compressed data without compromising performance. We show that the requirements on the file contents posed by pugz can be dropped by implementing an architecture based on a cache and a parallelized prefetcher. This architecture can safely handle faulty decompression results, which can appear when threads start decompressing in the middle of a gzip file by using trial and error. Using 128 cores, our implementation reaches 8.7 GB/s decompression bandwidth for gzip-compressed base64-encoded data, a speedup of 55 over the single-threaded GNU gzip, and 5.6 GB/s for the Silesia corpus, a speedup of 33 over GNU gzip.


Original languageEnglish
Title of host publicationHPDC 2023 - Proceedings of the 32nd International Symposium on High-Performance Parallel and Distributed Computing
Place of PublicationOrlando, FL, US
PublisherAssociation for Computing Machinery (ACM), New York
Number of pages13
ISBN (electronic)9798400701559
Publication statusPublished - 19 Jun 2023

External IDs

Scopus 85169612617