Greenlettask2

Greenlettask2 is a lightweight concurrency framework designed to coordinate multiple lightweight tasks within a single process using cooperative multitasking. The project follows a greenlet-inspired model, where tasks yield control to a central scheduler rather than relying on preemptive threading. This approach aims to provide predictable scheduling and low memory overhead for environments with limited resources.

At its core, greenlettask2 defines tasks as callables or coroutines that can yield execution to the scheduler. The scheduler maintains ready and wait queues, supports timeouts, and exposes APIs for creating, pausing, resuming, and canceling tasks. Tasks can form simple hierarchies, with parent tasks launching child tasks and awaiting their completion.

Features include a minimal API surface for task creation, cancellation tokens, timeout handling, task-local storage, and integration hooks for external event loops. The library emphasizes deterministic behavior and straightforward debugging, with built-in instrumentation for tracing task switches and exceptions.

Greenlettask2 originated as an open-source continuation of earlier lightweight-concurrency experiments. It targets use cases where traditional threads are too heavy or where a single-process event loop is preferred, such as embedded systems, test harnesses, and automation scripts.

Limitations include reliance on cooperative yields being honored by tasks, potential difficulty in debugging complex task interactions, and limited performance benefits for CPU-bound workloads. It is not a replacement for threaded parallelism in CPU-intensive applications.

See also: Greenlet, asyncio, cooperative multitasking, micro-threading.