Go: Building Web Applications

The cost of goroutines

As you work with goroutines, you might get to a point where you're spawning dozens or even hundreds of them and wonder if this is going to be expensive. This is particularly true if your previous experience with concurrent and/or parallel programming was primarily thread-based. It's commonly accepted that maintaining threads and their respective stacks can begin to bog down a program with performance issues. There are a few reasons for this, which are as follows:

• Memory is required just for the creation of a thread
• Context switching at the OS level is more complex and expensive than in-process context switching
• Very often, a thread is spawned for a very small process that could be handled otherwise

It's for these reasons that ...