Script, ScriptBlock and module performance profiler for PowerShell 5, and PowerShell 7 that works in Windows, Linux and MacOS.

Install the module from PowerShell gallery:

Install-Module Profiler

$trace =  Trace-Script -ScriptBlock { & "demo-scripts/MyScript.ps1" }
$trace.Top50Duration | Format-Table

• Profile module functions, or any scriptblock.

$scriptBlock = { 
    Import-Module Pester
    Invoke-Pester
}
Trace-Script -ScriptBlock $scriptBlock

(Excluding files, e.g. Pester internals from the profiling is coming later.)

• Run code multiple times, comparing performance before and after your changes.

$flag = @{ _profiler = $true }
Invoke-Script -ScriptBlock $scriptBlock -Preheat 0 -Repeat 3 -Flag $flag

• Look at a file or portion of a file

# to see the whole file 
$trace.Files[0].Profile | Format-Table

# or to get first 10 lines 
$trace.Files[0].Profile[0..9] | Format-Table

• Retrieve the last profile when you did not assign it to a variable

Invoke-Script -ScriptBlock $scriptBlock -Preheat 0 -Repeat 3 -Flag $flag

# Output:
# Looks like you did not assign the output to a variable. Use Get-LatestTrace to retrieve the trace, e.g.: $trace = Get-LatestTrace

$trace = Get-LatestTrace
$trace.Top50Duration | Format-Table

• Progress of your changes

Running profiling multiple times in a row keeps the previous times to show you your progress. Indicating Before and After with B and A.

• And more, like breakdown of a given line (.CommandHits), seeing who called given line (.Hits) and seeing the call stack that lead to the current call. All of them just need to be documented first.

Original prototype of this module is demoed here on Youtube The commands were renamed, but the way you can work with the resulting trace remained the same.

This module is under heavy development, it should stabilize soon because I will start writing tests. Here are some limitations of my current desing that I know how to fix, I just did not have time to do it yet:

• Files that are detected but don't exist anymore are skipped during the trace processing.
• This includes unsaved files in VSCode.
• Unbound scriptblocks cause null reference exceptions in the trace processing.
• Lines of internal code from the module may appear in the overview of the execution.