unsloth/studio/backend/utils/cpu_threads.py
alkinun 9222ffd9b4
Studio: add configurable CPU thread pool limit (#5760)
* Studio: add configurable CPU thread pool limit

* Studio: report invalid CPU thread setting cleanly

* Studio: also cover uvicorn main:app, harden tests, move docs to advanced

---------

Co-authored-by: Roland Tannous <115670425+rolandtannous@users.noreply.github.com>
Co-authored-by: danielhanchen <danielhanchen@gmail.com>
2026-05-27 05:09:34 -07:00

39 lines
1.3 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
"""Early CPU thread-pool configuration for Studio processes."""
import os
from typing import MutableMapping, Optional
_THREAD_POOL_ENV_VARS = (
"OMP_NUM_THREADS",
"MKL_NUM_THREADS",
"OPENBLAS_NUM_THREADS",
"NUMEXPR_NUM_THREADS",
)
def configure_cpu_threads(env: Optional[MutableMapping[str, str]] = None) -> None:
"""Apply ``UNSLOTH_CPU_THREADS`` to native CPU pools when configured.
This must run before importing libraries that initialize an OpenMP or
BLAS thread pool. Library-specific variables are left untouched so users
can override a single runtime independently.
"""
environ = os.environ if env is None else env
configured = environ.get("UNSLOTH_CPU_THREADS", "").strip()
if not configured:
return
try:
thread_count = int(configured)
except ValueError as exc:
raise ValueError("UNSLOTH_CPU_THREADS must be a positive integer") from exc
if thread_count < 1:
raise ValueError("UNSLOTH_CPU_THREADS must be a positive integer")
value = str(thread_count)
for variable in _THREAD_POOL_ENV_VARS:
environ.setdefault(variable, value)