Private/Where-ObjectFast.ps1
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# Module: TeamsFunctions # Function: Private Function for Testing purposes # Author: Dr. Tobias Weltner / PowerShellOne # Updated: N/A # Status: Unmanaged function Where-ObjectFast { <# .SYNOPSIS Faster Where-Object .DESCRIPTION Where-ObjectFast can replace the built-in Where-Object and improves pipeline speed considerably. Where-ObjectFast supports only the scriptblock version of Where-Object, so you can replace Get-Service | Where-Object { $_.Status -eq 'Running' } with Get-Service | Where-ObjectFast { $_.Status -eq 'Running' } but you cannot currently replace the short form of Where-Object: Get-Service | Where-Object Status -eq Running Where-ObjectFast has a performance benefit per iteration, so the more objects you send through the pipeline, the more significant performace benefits you will see. Where-ObjectFast is using a steppable pipeline internally which performs better. However because of this, the debugging experience will be different, and internal variables such as $MyInvocation may yield different results. For most every-day tasks, these changes are not important. A complete explanation of what Where-ObjectFast does can be found here: https://powershell.one/tricks/performance/pipeline .EXAMPLE $stopwatch = [System.Diagnostics.Stopwatch]::StartNew() $result = 1..1000000 | Where-ObjectFast -FilterScript { $_ % 5 } $report = '{0} elements in {1:n2} seconds' $report -f $result.Count, $stopwatch.Elapsed.TotalSeconds Demos the speed improvements. Run this script to see how well it performs, then replace Where-ObjectFast with the default Where-Object, and check out the performace difference. $result is the same in both cases. .LINK https://powershell.one/tricks/performance/pipeline https://github.com/TobiasPSP/Modules.PSOneTools/blob/master/PSOneTools/1.2/Where-ObjectFast.ps1 #> [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseApprovedVerbs', '', Justification = 'This is used for testing purposes')] param ( # Filter scriptblock that is applied to each pipeline element. # When the filter scriptblock evaluates to $true, the element can pass, # else the element is filtered out. [ScriptBlock] $FilterScript ) begin { # construct a hard-coded anonymous simple function: $code = @" & { process { if ($FilterScript) { `$_ } } } "@ # turn code into a scriptblock and invoke it # via a steppable pipeline so we can feed in data # as it comes in via the pipeline: $pip = [ScriptBlock]::Create($code).GetSteppablePipeline($myInvocation.CommandOrigin) $pip.Begin($true) } process { # forward incoming pipeline data to the custom scriptblock: $pip.Process($_) } end { $pip.End() } } |