RunSpace及其闭包

Question

在使用使用RunSpace的脚本时，我发现它占用了越来越多的系统内存。据我所知，这是因为开放的RunSpace在完成时不关闭。它们仍然存在于记忆中，积累着兆字节。

如何正确关闭RunSpace？但是，我不知道需要多长时间-1秒或1小时。当完成时关闭自己。

举个例子，我将给出任意脚本。

第一个脚本是我如何在RunSpace完成时关闭它(显然它不起作用)。

$Array = 1..10000

$PowerShell = [PowerShell]::Create()
$RunSpace = [Runspacefactory]::CreateRunspace()
$RunSpace.Open()

$RunSpace.SessionStateProxy.SetVariable('Array', $Array)
$RunSpace.SessionStateProxy.SetVariable('PowerShell', $PowerShell)

$PowerShell.Runspace = $RunSpace

[void]$PowerShell.AddScript({

   # Fill the system memory so that it can be seen in the Task Manager.
   $Array += $Array
   $Array

   # Closing the Process, which should close the RunSpace, but this does not happen.
   $Powershell.Runspace.Dispose()
   $PowerShell.Dispose()
})

$Async = $PowerShell.BeginInvoke()

# Other jobs in the main thread...

从系统内存来看，第二个脚本似乎更正确。然而，它当然不适用于生活，因为Start-Sleep 10冻结了主要的过程。

$Array = 1..10000

$PowerShell = [PowerShell]::Create()
$RunSpace = [Runspacefactory]::CreateRunspace()
$RunSpace.Open()

$RunSpace.SessionStateProxy.SetVariable('Array', $Array)

$PowerShell.Runspace = $RunSpace

[void]$PowerShell.AddScript({

   # Fill the system memory so that it can be seen in the Task Manager.
   $Array += $Array
   $Array
})

$Async = $PowerShell.BeginInvoke()

Start-Sleep 10

$PowerShell.EndInvoke($Async) | Out-Null
$PowerShell.RunSpace.Dispose()
$PowerShell.Dispose()

# Other jobs in the main thread...

请给我写正确的方式关闭RunSpace，因为它已经完成。谢谢你

Answer 1

试图从运行空间中释放运行空间听起来是个坏主意--事实上，如果我在PowerShell Core7.0-Rc2中尝试这个操作，我的会话就会挂起。

听起来像是--您想要自动释放运行空间，脚本的 on completion 。

您可以为System.Management.Automation.PowerShell.InvocationStateChanged事件设置一个事件处理程序，在其中您可以检查Completed和Failed状态，然后关闭运行空间：

注意:必须使用Register-ObjectEvent来订阅事件；虽然原则上可以通过将脚本块直接传递给PowerShell实例上的.add_InvocationStateChanged()来订阅，但稍后调用.EndInvoke()时执行将挂起。

# Note: I'm using a small array so that the output of the code better
#       shows what's happening.
$Array = 1..3

$PowerShell = [PowerShell]::Create()
$RunSpace = [Runspacefactory]::CreateRunspace()
$RunSpace.Open()

$RunSpace.SessionStateProxy.SetVariable('Array', $Array)

$PowerShell.Runspace = $RunSpace

$null = $PowerShell.AddScript( {

    # Fill the system memory so that it can be seen in the Task Manager.
    $Array += $Array
    $Array

  })

# Set up an event handler for when the invocation state of the runspace changes.
# Note: Register-ObjectEvent with -Action returns an event-job object, which
#       we don't need in this case.
$null = Register-ObjectEvent -InputObject $PowerShell -EventName InvocationStateChanged -Action {
  param([System.Management.Automation.PowerShell] $ps)

  # NOTE: Use $EventArgs.InvocationStateInfo, not $ps.InvocationStateInfo, 
  #       as the latter is updated in real-time, so for a short-running script
  #       the state may already have changed since the event fired.
  $state = $EventArgs.InvocationStateInfo.State

  Write-Host "Invocation state: $state"
  if ($state -in 'Completed', 'Failed') {
    # Dispose of the runspace.
    Write-Host "Disposing of runspace."
    $ps.Runspace.Dispose()
    # Speed up resource release by calling the garbage collector explicitly.
    # Note that this will pause *all* threads briefly.
    [GC]::Collect()
  }      

}

# Kick off execution of the script and
# let the event handler dispose of the runspace on completion.
Write-Host 'Starting script execution via SDK...'
$asyncResult = $PowerShell.BeginInvoke()

# Perform other processing.
Write-Host 'Doing things...'
1..1e5 | ForEach-Object { }

# Finally, get the results from the script execution.
# NOTE: Even though the runspace has likely already been disposed, collecting
#       the results seemingly still works.
Write-Host 'Collecting script-execution results...'
$PowerShell.EndInvoke($asyncResult)

# Note that you'll have to create and assign a *new* runspace to 
# $PowerShell.Runspace if you want to execute further code.

Write-Host 'Done.'

以上所述应产生以下输出：

Starting script execution via SDK...
Doing things...
Invocation state: Running
Invocation state: Completed
Disposing of runspace.
Collecting script-execution results...
1
2
3
1
2
3
Done.