is there a way to force

withContext(<http://Dispatchers.IO|Dispatchers.IO>)

onto a new thread? applies to

GlobalScope.future(<http://Dispatchers.IO|Dispatchers.IO>)

etc as well

Why do you need to?

hmmm assume I have 4 default dispatcher workers; and I ended up making a blocking call on all of them like

CompletableFuture.get()

DefaultDispatcher-worker-1 .get() DefaultDispatcher-worker-2 .get() DefaultDispatcher-worker-3 .get() DefaultDispatcher-worker-4 .get() now unfortunately, due to "reasons", these completablefutures are from

GlobalScope.future(<http://Dispatchers.IO|Dispatchers.IO>) { }

and none of these can spawn because

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

should not context switch, but because all DefaultDispatcher-workers are blocked, there's a deadlock there are obviously better and correct-er ways of fixing this; but out of curiosity, if

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

spawn wasn't blocked on

Dispatchers.Default

this could probably be avoided

Don't make blocking calls like

CompletableFuture.get()

on the default dispatcher. Use the suspending

await

extension for `CompletableFuture`: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-jdk8/.

well, duh. but that's not what this question's about.

There's no way to force a context switch here. You can try to avoid deadlock by creating a separate dispatcher with its own pool of threads, but, of course, writing code so that it is not deadlock-prone in the first place is better.

I know this seems like an XY problem at first, but this is bad and botched attempts at mingling blocking and non-blocking code that has accumulated over two years; and there's no way to identify or fix all of it at once. thanks for clearing that up, I will look into putting these on a separate dispatcher apart from fixing the obvious instances of blocking calls on a non-blocking context.

Have you tried using Blockhound to identify the blocking calls? https://github.com/reactor/BlockHound. Coroutines integration via kotlinx-coroutines-debug: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-debug/.