Chapters/scripting-at-scale/pipelinesamples.ps1
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#demonstrate pipeline performance differences return "This is a demo script file." #region pipeline vs parameter $names = get-service | select -expand name #57ms measure-command { $names | get-service } #40ms measure-command { get-service $names } $big = $names+$names+$names+$names+$names #253ms measure-command { $big | get-service } #169ms measure-command { get-service $big } #endregion #region breakup a command #861ms Measure-Command { $data = dir $env:temp -file -Recurse | group extension | Sort Count | Select Count,Name,@{Name="Size";Expression = { ($_.group | Measure-object -Property length -sum).sum }} } #779 Measure-Command { $files = dir $env:temp -file -Recurse $grouped = $files | group extension $sorted = $grouped| Sort Count $data = $sorted | Select Count,Name,@{Name="Size";Expression = { ($_.group | Measure-object -Property length -sum).sum }} } #endregion #region ForEach vs Foreach-Object $n = 1..10000 #51.7ms Measure-command { $a = 0 foreach ($i in $n) { $a+=$i } } #227ms Measure-command { $n | foreach-object -Begin { $a = 0 } -process { $a+=$_ } } #endregion |