Module writer 

Dedicated writer task for high-throughput frame sending.

This module replaces the Arc<Mutex<BoxedWriter>> pattern with a dedicated writer task that receives frames via an mpsc channel. This eliminates lock contention and enables batching multiple frames into single syscalls.

Architecture

Handler 1 ─┐
Handler 2 ─┼─► mpsc::Sender<OutboundFrame> ─► Writer Task ─► Pipe
Handler N ─┘

Benefits

• No lock contention: Channel-based, not mutex-based
• Batching: Multiple frames can be written in a single syscall via writev
• Backpressure: Built-in pending count tracking with configurable limits

Structs

OutboundFrame

A frame ready to be written to the pipe.

WriterConfig

Configuration for the writer task.

WriterHandle

Handle for sending frames to the writer task.

Constants

DEFAULT_BACKPRESSURE_TIMEOUT

Default backpressure timeout.

DEFAULT_CHANNEL_CAPACITY

Default channel capacity.

DEFAULT_MAX_PENDING_FRAMES

Default maximum pending frames before backpressure kicks in.

Functions

spawn_writer_task

Spawn the writer task and return a handle for sending frames.

spawn_writer_task_default

Spawn the writer task with default configuration.