Recommendation for running an Effect on a DispatchQueue?

[alexdong]

Hi folks, we have a long-running background process that takes quite a while to execute (5min ~ 30min depends on the device). We built several prototypes to evaluate the correct way to structure this. It turns out that running it on a concurrent DispatchQueue via async was the most performant and memory-safe way. We had a version using Swift's new TaskGroup, but it didn't perform as well. Our current code looks like this

public class Processor {
  static let processorQueue = DispatchQueue(label: "keepers.Processor", attributes: .concurrent)

  init() { ... }
  public func run() { ... }
}

...

// To kick it off, we do 
Processor.processorQueue.async {
  Processor().run()
}

I'm wondering what's the right way to create an Effect to kick the task off in the TCA world. Reading through the Effect.run implementation, it looks like it uses TaskGroup under the hood.

Thanks,

Alex

[alexdong]

My current attempt is to fold the async inside the run(), so the code looks like the following:

public class Processor {
  static let processorQueue = DispatchQueue(label: "keepers.Processor", attributes: .concurrent)

  init() { ... }
  public func run() { 
    processorQueue.async {
      ...
    }
   }
}

@Dependency(\.processor) var processor
public func reduce(state, action) -> Effect<Action, Never> {
  switch action { 
    case .start:
      return .run { send in 
        processor.run()
      }
    }
  }
}