have bugs on Julia1.7

[magicly]

When I run https://github.com/jonathan-laurent/AlphaZero.jl on Julia 1.7， It will run out of cpu and dont progress.

Below is a minimal test(sometime it is ok, needs several times run). I think this may be sth with Julia 1.7 new task sheculers.

import Base.Threads: Atomic, atomic_add!
using ThreadPools

function test_threadpools(nworkers)
  tasks = []
  ret = []
  done_n = Atomic()
  nbg = 4
  for i = 1:nworkers
    tid = 2 + i % nbg
    println("mapreduce before tspawnat: $i, $tid")
    task = ThreadPools.@tspawnat tid begin
      println("mapreduce in thread: $tid, $(Threads.threadid())")
      t1 = time()
      while time() - t1 < 0.01
      end
      atomic_add!(done_n, 1)
      push!(ret, Threads.threadid())
    end
    push!(tasks, task)
  end
  wait.(tasks)
  println("done_n: $done_n")
  return ret
end
test_threadpools(64 * 10)

I test it on Ubuntu 18.04:

julia> versioninfo()
Julia Version 1.7.0
Commit 3bf9d17731 (2021-11-30 12:12 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-12.0.1 (ORCJIT, skylake)

Julia 1.6.x is ok.

[tro3]

Passes unit tests and your example on 1.7.1. Still an issue for you?