PowerShell run script simultaneously

Question

I created a PowerShell script to remove all files and folders older than X days. This works perfectly fine and the logging is also ok. Because PowerShell is a bit slow, it can take some time to delete these files and folders when big quantities are to be treated.

My questions: How can I have this script ran on multiple directories ($Target) at the same time?

Ideally, we would like to have this in a scheduled task on Win 2008 R2 server and have an input file (txt, csv) to paste some new target locations in.

Thank you for your help/advise.

The script

#================= VARIABLES ==================================================
$Target = \\share\dir1"
$OlderThanDays = "10"
$Logfile = "$Target\Auto_Clean.log"

#================= BODY =======================================================
# Set start time
$StartTime = (Get-Date).ToShortDateString()+", "+(Get-Date).ToLongTimeString()

Write-Output "`nDeleting folders that are older than $OlderThanDays days:`n" | Tee-Object $LogFile -Append 

Get-ChildItem -Directory -Path $Target | 
    Where-Object { $_.LastWriteTime -lt (Get-Date).AddDays(-$OlderThanDays) } | ForEach {
        $Folder = $_.FullName
        Remove-Item $Folder -Recurse -Force -ErrorAction SilentlyContinue
        $Timestamp = (Get-Date).ToShortDateString()+" | "+(Get-Date).ToLongTimeString()      
        # If folder can't be removed
        if (Test-Path $Folder)
        { "$Timestamp | FAILLED: $Folder (IN USE)" } 
        else
        { "$Timestamp | REMOVED: $Folder" }  
        } | Tee-Object $LogFile -Append # Output folder names to console & logfile at the same time 

# Set end time & calculate runtime
$EndTime = (Get-Date).ToShortDateString()+", "+(Get-Date).ToLongTimeString()
$TimeTaken = New-TimeSpan -Start $StartTime -End $EndTime

# Write footer to log
Write-Output ($Footer = @"

   Start Time          : $StartTime
   End Time            : $EndTime
   Total runtime       : $TimeTaken
$("-"*79)
"@)

# Create logfile
Out-File -FilePath $LogFile -Append -InputObject $Footer

# Clean up variables at end of script
$Target=$StartTime=$EndTime=$OlderThanDays = $null

Answer 1

One way to achieve this would be to write an "outer" script that passes the directory-to-be-cleaned, into the "inner" script, as a parameter.

For your "outer" script, have something like this:

$DirectoryList = Get-Content -Path $PSScriptRoot\DirList;
foreach ($Directory in $DirectoryList) {
    Start-Process -FilePath powershell.exe -ArgumentList ('"{0}\InnerScript.ps1" -Path "{1}"' -f $PSScriptRoot, $Directory);
}

Note: Using Start-Process kicks off a new process that is, by default, asynchronous. If you use the -Wait parameter, then the process will run synchronously. Since you want things to run more quickly and asynchronously, omitting the -Wait parameter should achieve the desired results.

Invoke-Command

Alternatively, you could use Invoke-Command to kick off a PowerShell script, using the parameters: -File, -ArgumentList, -ThrottleLimit, and -AsJob. The Invoke-Command command relies on PowerShell Remoting, so that must enabled, at least on the local machine.

---

Add a parameter block to the top of your "inner" script (the one you posted above), like so:

param (
    [Parameter(Mandatory = $true)]
    [string] $Path
)

That way, your "outer" script can pass in the directory path, using the -Path parameter for the "inner" script.