multithreadingpowershellparallel-processing

Can Powershell Run Commands in Parallel?

I have a powershell script to do some batch processing on a bunch of images and I'd like to do some parallel processing. Powershell seems to have some background processing options such as start-job, wait-job, etc, but the only good resource I found for doing parallel work was writing the text of a script out and running those (PowerShell Multithreading)

Ideally, I'd like something akin to parallel foreach in .net 4.

Something pretty seemless like:

foreach-parallel -threads 4 ($file in (Get-ChildItem $dir))
{
   .. Do Work
}

Maybe I'd be better off just dropping down to c#...

Solution

  • You can execute parallel jobs in Powershell 2 using Background Jobs. Check out Start-Job and the other job cmdlets.

    # Loop through the server list
Get-Content "ServerList.txt" | %{
 
  # Define what each job does
  $ScriptBlock = {
    param($pipelinePassIn) 
    Test-Path "\\$pipelinePassIn\c`$\Something"
    Start-Sleep 60
  }
 
  # Execute the jobs in parallel
  Start-Job $ScriptBlock -ArgumentList $_
}
 
Get-Job
 
# Wait for it all to complete
While (Get-Job -State "Running")
{
  Start-Sleep 10
}
 
# Getting the information back from the jobs
Get-Job | Receive-Job