Why Doesn\'t My Go Routine with `select` Stop Without `fmt.Print()`?

Go Routine with Select Doesn't Stop Unless Fmt.Print() Is Added

In this Go exercise, we encounter a peculiar issue where a goroutine using select doesn't halt until an additional fmt.Print() statement is introduced. To understand this behavior, let's delve into the underlying mechanics of select within a goroutine.

Without a default statement, select blocks until there are messages on all the channels. However, a default statement allows select to execute a default action if none of the channels have messages. In the provided code, this default statement becomes an infinite loop, consuming the execution pipeline of the scheduler.

The fmt.Print() statement provides a way for the scheduler to temporarily release the goroutine, allowing other goroutines to run. Without this release, the scheduler becomes stuck in the infinite loop within the select statement.

To address this issue, one can either remove the default statement to make the select non-blocking or introduce a temporary release mechanism such as fmt.Print(). Furthermore, using GOMAXPROCS=2 can mitigate the problem by increasing the number of available execution threads, but this approach doesn't fully resolve the issue.

Note that goroutines are cooperatively scheduled, meaning they yield control voluntarily. It's unclear why the select statement doesn't yield in the original code, despite presenting an opportunity for the goroutine to do so.

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