Jobs

PowerShell · Reference cheat sheet

📋 Overview

Jobs run work in the background. Classic jobs (Start-Job) use separate processes; thread jobs (Start-ThreadJob) are lighter. PowerShell 7 also offers ForEach-Object -Parallel. Use jobs for fan-out, long tasks, and remoting aggregation.

🔧 Core concepts

Child jobs appear under parent job objects for remoting fan-out. Always Receive-Job + Remove-Job to avoid leaks.

💡 Examples

Local jobs:

$j = Start-Job -ScriptBlock {
  Start-Sleep -Seconds 2
  Get-Date
}
Wait-Job $j | Out-Null
Receive-Job $j
Remove-Job $j

ThreadJob:

Install-Module ThreadJob -Scope CurrentUser
$jobs = 1..5 | ForEach-Object {
  Start-ThreadJob { param($n) Start-Sleep 1; $n * 2 } -ArgumentList $_
}
$jobs | Wait-Job | Receive-Job
$jobs | Remove-Job

Parallel foreach (PS 7+):

1..10 | ForEach-Object -Parallel {
  Invoke-RestMethod "https://httpbin.org/get?n=$_"
} -ThrottleLimit 4

⚠️ Pitfalls

• Jobs don’t share live variables with the parent—pass -ArgumentList or $using: (remote/parallel).
• Forgetting Receive-Job leaves output buffered and jobs in Completed state forever.
• Start-Job is heavy (new runspace/process)—prefer ThreadJob/parallel for many small tasks.
• Errors surface when receiving—check job State and ChildJobs.
• UI/host-interactive cmdlets fail inside jobs.
• Remoting jobs need sessions cleaned up (Remove-PSSession).

🔗 Related

• remoting.md
• loops.md
• error_handling.md
• scripting.md
• pipeline.md