Move task cancelation on blocking pool

[danilbykov]

Now task cancelation is executed on main vertx pool. But task cancelation may be blocking operation. Here is such example:

import zio._
import zio.blocking.Blocking

val task =
   for {
     blocking <- ZIO.service[Blocking.Service]
     _ <- blocking.effectBlocking({
       println(Thread.currentThread().getName())
       Thread.sleep(5000)
       println("end")
     })
  } yield ()

val runtime = Runtime.default

val canceler = runtime.unsafeRunAsyncCancelable(task) { _ => () }

canceler(Fiber.Id.None) // this call is blocked by Thread.sleep(5000)

So interrupting of several tasks may block main vertx pool and leads to following warnings

Thread Thread[vert.x-eventloop-thread-1,5,zio-default-async] has been blocked for 6381 ms, time limit is 2000 ms

So it is better to execute this operation on blocking pool.

[danilbykov]

I noted that new temp file is created each time when server is started. It seems that it is equivalent code to get temp dir.

[adamw]

makes sense, thanks :)

[adamw]

actually the same code is present in cats & future interpreters, so maybe we could make ew java.io.File(System.getProperty("java.io.tmpdir")) an internal utility function and simply use it in these places

[danilbykov]

OK. I moved this line inside function VertxServerOptions.uploadDirectory()

[adamw]

Thanks! Shouldn't we do the same in VertxCatsServerInterpreter ?

[danilbykov]

It looks like this issue is not applied for VertxCatsServerInterpreter because CancelToken is function from Unit to Future[Unit]. So calling such function doesn't block caller and just returns Future.

[adamw]

Ah ok:)

[adamw]

Thanks!