Deploying Python based AI agents on resource-constrained edge devices presents a runtime optimization challenge: high thread counts are needed to mask I/O latency, yet Python's Global Interpreter Lock (GIL) serializes execution. We demonstrate that naive thread-pool scaling causes a "saturation cliff": >= 20% throughput degradation at overprovisioned thread counts (N >= 512) on edge-representative configurations. We present a lightweight profiling tool and adaptive runtime system using a Blocking Ratio metric (beta) that distinguishes genuine I/O wait from GIL contention. Our library-based solution achieves 96.5% of optimal performance without manual tuning, outperforming multiprocessing (limited by ~8x memory overhead on devices with 512 MB-2 GB RAM) and asyncio (blocked by CPU-bound phases). Evaluation across seven edge AI workload profiles, including real ML inference with ONNX Runtime MobileNetV2, demonstrates 93.9% average efficiency. Comparative experiments with Python 3.13t (free threading) show that while GIL elimination enables ~4x throughput on multi-core edge devices, the saturation cliff persists on single-core devices, validating our beta metric for both GIL and no-GIL environments. This provides practical optimization for edge AI systems.
翻译:在资源受限的边缘设备上部署基于Python的AI代理面临运行时优化挑战:需要高线程数以掩盖I/O延迟,但Python的全局解释器锁(GIL)会串行化执行。我们证明,简单的线程池扩缩会导致"饱和悬崖":在具有边缘代表性配置的超量线程数(N ≥ 512)下,吞吐量下降≥20%。我们提出了一种轻量级分析工具和自适应运行时系统,使用阻塞率指标(β)来区分真实的I/O等待与GIL争用。我们基于库的解决方案无需手动调优即可实现96.5%的最佳性能,优于多进程方案(受限于512 MB-2 GB内存设备上约8倍的内存开销)和asyncio(受CPU密集型阶段阻塞)。通过对七种边缘AI工作负载配置(包括使用ONNX Runtime MobileNetV2的真实ML推理)的评估,平均效率达到93.9%。与Python 3.13t(自由线程)的对比实验表明,虽然GIL消除能在多核边缘设备上实现约4倍吞吐量,但在单核设备上饱和悬崖依然存在,这验证了我们的β指标在GIL和无GIL环境中的普适性。这为边缘AI系统提供了实用的优化方案。