Goroutines feel free.

We create them without hesitation. We use them to parallelize work, reduce latency, and simplify complex logic. But what does a goroutine actually cost? What happens when you create thousands? Or millions?

In this talk, we will explore the real cost of Go’s most beloved abstraction. We will examine how goroutine stacks are allocated and grown, how the scheduler distributes work, how preemption works, and how memory pressure affects runtime behavior. We will also investigate subtle production issues such as runaway concurrency, goroutine leaks, scheduler contention, and unexpected memory growth.

This session is not a warning against concurrency. It is a deeper understanding of it.

By building a concrete mental model of how goroutines behave at scale, you will learn how to reason about concurrency in high-throughput systems. You will leave with practical techniques for bounding parallelism, avoiding leaks, and designing systems that cooperate with the runtime instead of overwhelming it.

Goroutines are cheap.
They are not free.