Faster Python on Azure Functions with uvloop

Azure Functions now offers improved performance for Python 3.13+ applications. This enhancement is achieved by replacing the standard asyncio event loop with uvloop by default. Uvloop, built on libuv, provides a high-performance alternative to the default Python event loop. This change results in increased throughput and reduced latency for asynchronous workloads. Consequently, Azure Functions Python apps become faster and more responsive without any code modifications. The event loop is crucial for managing asynchronous tasks and concurrency in serverless applications. Uvloop's Cython implementation offers significant performance gains over the default UnixSelectorEventLoop. The Azure Functions Python worker automatically sets uvloop as the default event loop policy upon startup for Python 3.13 and above. This means all asynchronous operations automatically benefit from uvloop's optimizations. Extensive testing demonstrates measurable improvements in request handling and sustained load scenarios. Uvloop was chosen as the default for Python 3.13+ to ensure a net positive performance impact and ease of rollout.