Programming Tutorials

  For over a decade, the idiomatic way to implement lazy generators or data pipelines in Go was the "concurrency pattern": spin up a goroutine, push data into a channel, and close the channel when done. While elegant, this pattern abuses Go's concurrency primitives for sequential logic. Using channels for simple iteration incurs significant performance penalties: heavy Garbage Collector (GC) pressure from short-lived goroutine stacks, scheduler overhead (context switching), and the risk of goroutine leaks if the consumer exits early. With Go 1.23, the standard library introduced the  iter  package. This allows us to refactor push-based channel generators into pull-based iterators, eliminating the concurrency overhead entirely while maintaining the ergonomics of  for-range  loops. The Root Cause: Why Channels Are Expensive for Iteration When you use a channel merely to stream data from point A to point B without parallel processing, you incur costs at three layer...

  The choice between Shared State ( Arc<Mutex<T>> ) and Message Passing (Channels) is the most common architectural deadlock in Rust development. The Go mantra—"Do not communicate by sharing memory; share memory by communicating"—often misleads Rust developers into forcing everything through channels. Conversely, developers coming from C++ or Java often default to complex hierarchies of Mutexes, leading to deadlocks and high contention. The reality is that strict adherence to one pattern creates sub-optimal systems. High-performance Rust architectures almost always require a hybrid approach:  Channels for Control Flow, Mutexes for State. The Root Cause: Contention vs. Ownership To resolve the paralysis, we must understand what happens at the hardware and ownership level when you choose one over the other. 1. The Cost of Shared State (Mutex) When you wrap data in  Arc<Mutex<T>> , you are enforcing serial access. Logical Consequence:  If the cri...