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Version: latest

Profiling (minimal, deterministic)

X07 includes a minimal function profiler intended for reproducible “what got slower?” investigations without relying on wall-clock timing.

Enable it by setting:

  • X07_PROFILE=1

Note: this profiler is compile-time instrumentation. X07_PROFILE must be set when the program is compiled/bundled. For x07 run, setting it on the same command works because x07 run compiles then executes.

When enabled, the generated runtime prints one JSON line to stderr at program exit:

  • schema_version: "x07.profile.fn@0.1.0"
  • per-function counters:
    • calls
    • fuel_excl (exclusive fuel; deterministic “time” unit)
    • alloc_calls_excl
    • alloc_bytes_excl

Usage​

Example:

X07_PROFILE=1 x07 run --profile os

Notes​

  • The unit is fuel, not wall time. Fuel is deterministic for deterministic inputs and code paths.
  • The profiler instruments solve and user-defined defn functions.
  • Native backends (for example filesystem/archive adapters) are not included in these counters.
  • If the process terminates early (for example a trap), the profile line may not be emitted.