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arXiv · 2102.13516

AwkwardForth: accelerating Uproot with an internal DSL

Jim Pivarski·Ianna Osborne·Pratyush Das·David Lange·Peter Elmer
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Abstract

File formats for generic data structures, such as ROOT, Avro, and Parquet, pose a problem for deserialization: it must be fast, but its code depends on the type of the data structure, not known at compile-time. Just-in-time compilation can satisfy both constraints, but we propose a more portable solution: specialized virtual machines. AwkwardForth is a Forth-driven virtual machine for deserializing data into Awkward Arrays. As a language, it is not intended for humans to write, but it loosens the coupling between Uproot and Awkward Array. AwkwardForth programs for deserializing record-oriented formats (ROOT and Avro) are about as fast as C++ ROOT and 10-80$\times$ faster than fastavro. Columnar formats (simple TTrees, RNTuple, and Parquet) only require specialization to interpret metadata and are therefore faster with precompiled code.

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Jim Pivarski, Ianna Osborne, Pratyush Das, David Lange, Peter Elmer. 2021-02-24. AwkwardForth: accelerating Uproot with an internal DSL. https://doi.org/10.1051/epjconf/202125103002

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