I am honestly confused about what dispatchers to use server-side. Everything I have read so far has been focused on Android. Any recommendations for a general guide to when to use what dispatcher?

As a rule of thumb : •

Dispatchers.Main

may not exist on the server-side. •

Dispatchers.Default

should be used for computational tasks that requires CPU power such as reducing, transforming, etc. It has a pool of thread equal to the number of CPU cores to avoid overloading the CPU when scheduling too much work. •

<http://Dispatchers.IO|Dispatchers.IO>

, as its name suggests, should be used for blocking IO such as database access, file read/write and network communication. It has a larger pool of threads than

Default

because IO tasks don't need much CPU time, it just waits and blocks a thread.

Thanks. what about long or continuously running coroutines, that stream values on a schedule?

I think you can run that on

<http://Dispatchers.IO|Dispatchers.IO>

since it has the largest thread pool and your task requires some network connectivity. You could write it this way:

launch(<http://Dispatchers.IO|Dispatchers.IO>) {
    while(true) {
        postStatusUpate(...)
        delay(10 * 60 * 1000) // 10 minutes in milliseconds
    }
}

Note that while the coroutine is suspended in

delay

it is not actively using a thread.

👍