示例
Configure joblib parallel execution with parallel_config and verify backend constraint resolution, nested context propagation, and failure modes on contradictory settings.
sha256:358ff91d26968481475e6fb33480225b3c25f6adba6d6bb2170118ee39c4a2de
发布状态。LOCAL_PASS 表示仅在作者环境中通过；PUBLISHED 表示已公开并等待独立验证；CROSS_PASS 表示另一验证者已复现；MATRIX_PASS 表示在不同环境中通过；STABLE 表示近期无失败且独立通过持续稳定。
证据强度。L0 仅有源码；L1 已解析依赖；L2 已编译或加载；L3 已通过契约；L4 已被独立复现；L5 已在不同环境中通过。
MIT-0
执行证据
分开显示声明环境和签名验证运行，明确样本的证明范围。
- 证据依据
- 独立交叉验证
- 验证回执
- 2
- 验证级别
- L4_CROSS_PASS
声明的环境
python linux x64 python python pip
验证运行环境
| 环境 | 契约 | 阶段 | 运行日期 |
|---|---|---|---|
| python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-19 |
| python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · python@1 |
2026-08-19 |
案例
HOW- 目标
- Configure joblib parallel execution with parallel_config and verify backend constraint resolution, nested context propagation, and failure modes on contradictory settings.
- 符号
-
- joblib.parallel_config
- joblib.Parallel
- joblib.delayed
- joblib.parallel.get_active_backend
- 环境
- python
- 创建时间
- 2026-08-19T13:42:06Z
契约
- Setting prefer='threads' in parallel_config with n_jobs=4 switches to ThreadingBackend but silently resets implicit n_jobs in context to 1, while explicit backend='threading' preserves n_jobs=4.
- Explicitly passing n_jobs=4 to Parallel overrides the thread fallback reset back to 4.
- Setting require='sharedmem' without an explicit backend forces ThreadingBackend and resets implicit n_jobs to 1.
- Contradictory settings prefer='processes' and require='sharedmem' raise ValueError on Parallel instantiation.
- Instantiating Parallel(backend='multiprocessing', require='sharedmem') raises ValueError, whereas configuring the same settings under parallel_config silently downgrades to ThreadingBackend and resets n_jobs to 1.
- Nested parallel_config scopes override configuration parameters within their block and restore outer context settings upon exit.
- Passing backend constructor parameters such as inner_max_num_threads without an explicit backend raises ValueError at context entry.
- Passing an unregistered backend name to parallel_config raises ValueError immediately at context entry.
文件
- NOTES.md
- csx.json
- requirements.txt
- test/contract.py