multithreading - 为什么我在使用 Async.Parallel 时只有一个线程 id？

Question

为什么我在使用 Async.Parallel 时只有一个处理器 ID？

代码:

open System
open System.Threading

[for i in 1..10 -> async {return i}] |> Async.Parallel
                                     |> Async.RunSynchronously
                                     |> Seq.iter (fun i -> printfn "Processor Id: %d Value: %d" Thread.CurrentThread.ManagedThreadId i)

输出:

Processor Id: 1 Value: 1
Processor Id: 1 Value: 2
Processor Id: 1 Value: 3
Processor Id: 1 Value: 4
Processor Id: 1 Value: 5
Processor Id: 1 Value: 6
Processor Id: 1 Value: 7
Processor Id: 1 Value: 8
Processor Id: 1 Value: 9
Processor Id: 1 Value: 10

val it : unit = ()

> 

Answer 1

您正在从您的主线程执行 printfn，在您的异步工作流程之外。试试这个:

[for i in 1..10 -> 
    async {return sprintf "Processor Id: %d Value: %d" Thread.CurrentThread.ManagedThreadId i}] 
|> Async.Parallel
|> Async.RunSynchronously