$ show tokio-rs/tokio
Tokio is a production-grade asynchronous runtime for Rust, providing the foundation for building reliable network applications, web servers, and concurrent systems. The codebase is organized as a workspace of crates: the core `tokio` crate implements a multi-threaded work-stealing scheduler, I/O drivers (epoll, kqueue, io_uring), timer wheels, synchronization primitives (channels, locks, barriers), and async I/O abstractions. Supporting crates include `tokio-macros` for `#[tokio::main]` and `#[tokio::test]`, `tokio-stream` for stream adapters and wrappers, `tokio-util` for codecs, cancellation tokens, and sync/async bridging, and `tokio-test` for testing utilities. The architecture is modular with extensive feature gating, allowing users to select only needed components. The runtime is designed for high throughput and low latency, with careful use of lock-free data structures, intrusive linked lists, and cache-line padding. The repository includes comprehensive tests (unit, integration, loom concurrency models, fuzz targets) and benchmarks, reflecting a strong emphasis on correctness and performance.
The LLM identified 6 files worth highlighting for reuse:
Provides zero-cost wrappers to convert between tokio's AsyncRead/AsyncWrite and futures' AsyncRead/AsyncWrite traits. Uses pin projection and manual trait implementation without allocation, enabling interoperability between the two ecosystems. Reusable in any project that needs to bridge tokio and futures I/O.
Implements a hierarchical cancellation token with parent-child propagation. Supports creating child tokens, awaiting cancellation, and running futures until cancelled. Uses a lock-free tree structure with careful deadlock avoidance. Reusable for any async application needing cooperative cancellation.
Adapts async I/O types (AsyncRead, AsyncWrite, AsyncBufRead) to synchronous std::io traits using Handle::block_on. Provides a safe, efficient bridge for code that needs to mix sync and async I/O. Reusable in any project that needs to call async I/O from synchronous contexts.
A collection of named streams that can be polled together, yielding items with their associated keys. Supports inserting, removing, and polling multiple streams concurrently. Reusable for fan-out patterns where multiple sources need to be processed with identity.
An intrusive doubly-linked list implementation used internally by the timer wheel, inject queue, and other scheduler components. Provides safe abstractions over raw pointers with loom-aware testing. Reusable in any Rust project needing a performant intrusive list.
A safe wrapper around a byte buffer that tracks both filled and initialized regions, enabling incremental reads without undefined behavior. Used by all async read operations in tokio. Reusable in any I/O library that needs to manage partially filled buffers.