numbarrow.core.configurations

Overview

Default Numba JIT compilation options shared across all @njit decorated functions in numbarrow.

Module

Default configuration options for Numba JIT compilation used throughout numbarrow.

numbarrow.core.configurations.get_jit_options()

Numba JIT options taken from the NUMBARROW_JIT_OPTIONS environment variable.

The value must be a JSON object and is passed to @njit as keyword arguments unchanged, for example export NUMBARROW_JIT_OPTIONS='{"cache": false}'. Unset or empty means {"cache": True}; anything else raises ValueError. The object replaces the default rather than extending it, so '{}' turns caching off. "cache" must be a JSON boolean: numba reads the string "false" as true, so it is refused rather than passed on, and so is a string for any other option but "error_model" and "inline", the two numba reads as strings: {"boundscheck": "false"} would turn bounds checking on. Each call reads the environment afresh; the module-level jit_options holds the value read when this module was first imported, and that is what the decorators use.

numba’s on-disk cache index records a function’s signature, target and bytecode but not the options it was compiled with, so a cache warmed under one set of options is a hit for a run that asked for another: {"cache": true, "boundscheck": true} over a directory warmed with the default loads the unchecked code. Point NUMBA_CACHE_DIR at a fresh directory when an option changes.