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I’ve got a new crash on ios in Kotlin 1.3.70 in coroutines. Here is the top of the stack

<@UF6SAV9J7> I don’t know if it’s related to the usage of CoroutineWorker or not

Sans titre

Here is how I use CoroutineWorker. I have multiple instances of this class (somewhere between 4 and 10). Most of the time `executeJobs()` does nothing (basically a `forEach` on a Stately `sharedMutableList()` which is empty most of the time)

The crash occurs after some minutes of execution of the app

hard to tell exactly. might be the delay usage in CoroutineWorker now overflows the stack

can i see the implementation of executeJobs?

In this case it handles file jobs
```    private fun executeJobs() {
        if (queue.isEmpty()) return
        val jobs = queue.toList()
        jobs.forEach { job -&gt;
            when (job) {
                is WriteJob -&gt; {
                    try {
                        job.file.writeRaw(job.content, create = true, createParents = true)
                    } catch (t: Throwable) {
                        log.error("Failed to write file ${job.file}: ${t.message}", t)
                    }
                }
                is DeleteJob -&gt; {
                    try {
                        job.file.delete()
                    } catch (t: Throwable) {
                        log.error("Failed to delete file ${job.file}: ${t.message}", t)
                    }
                }
            }
        }
        queue.removeAll(jobs)
    }```

At first I wanted to have a single `CoroutineWorker.execute` per instance which would run an infinite loop waiting on a shared collection, but CoroutineWorker is hardcoded to 4 threads and I need more than 4 and it was deadlocking somehow (I thought that using `delay` would allow a different execute block to continue execution but it didn’t work)

But in the end this solution worked well in 1.3.61 and now this

Is there any way you can provide a sample project and file an issue? At this point, I don't think there's much I can do on slack. Issue seems quite complex. Even if the sample project just runs the crashing code in a unit test, that would be helpful

An issue to allow setting the number of threads would be good too. That wouldn't be hard to add

Even if you can't make a sample project, moving to GH is prob best

I just have no way to know where this comes from for sure, it may as well be a bug in coroutines 1.3.4/1.3.5 or in my code, I don’t know. It will be very hard to make a reproducer I think but I’ll try if I have the time at some point. For now due to this issue and others I need to rollback to 1.3.61 to be able to work at all. Maybe once this issue is the only one preventing me from updating Kotlin I’ll try

Sounds good! No rush. If Kotlin 1.3.71 is followed by the kotlinx.coroutines native multithreading mpp release (as is expected), coroutineworker will become deprecated (just a heads up)

Yes, I’m really waiting for this, but I’m not expecting something this big to be very stable at first either