Tag Archives: Parallel

Massive Microsoft 365 groups update with PowerShell

What if you need to bulk update Microsoft 365 groups membership e.g. to add a group owner or member for tens of thousands m365 groups? Iterating through groups one-by-one is unproductive and could take days. Can we do it faster? Here is what I found.

In my case, it was Microsoft 365 ownerless groups policy implementation for large tenant… Skipping details – I needed to update ownership for 10,000 Microsoft 365 groups and I was looking for a best/fastest possible option maybe some kind of bulk update or with multiple threads. And I figured out that the fastest way is to use PnP.PowerShell that calls Microsoft Graph API but run it against list of groups with PowerShell parallel trick. Here is the sample PowerShell code:

$groups | ForEach-Object -Parallel {
    $owner = "newGroupOwnerUPN@contoso.com"
    Add-PnPMicrosoft365GroupOwner -Identity $_.Id -Users $owner
} -ThrottleLimit 50

That worked for me perfectly and it took ~8 seconds per 1,000 groups.

Update Large Number of SharePoint Sites with PowerShell Parallel

Get sites details

Now let us test, how long it takes to get sites details with Get-PnPTenantSite (I use a sample set of 500 sites):

Test type	Regular (Sequential), seconds per site	Parallel sample = 100 sites, seconds per site	Parallel sample = 200 sites, seconds per site	Parallel sample = 500 sites, seconds per site
Regular (Sequential)	0.65
Parallel, ThrottleLimit = 2		0.40	0.33	0.31
Parallel, ThrottleLimit = 5		0.17	0.14	0.36 (errors)
Parallel, ThrottleLimit = 10		0.11 (errors)	0.11 (errors)	0.34 (errors)
Parallel, ThrottleLimit = 20		0.12 errors+	0.07 errors+	0.52 (errors)

(errors) means there were small number of errors during test… e.g.

PnP.PowerShell Batches and PowerShell 7 Parallel

1 Reply

Parallelism

Can I use PowerShell 7 “-Parallel” option against SharePoint list items with PnP.PowerShell? Can I run something like:

$items | ForEach-Object -Parallel {
    $listItem = Set-PnPListItem -List "LargeList" -Identity $_ -Values @{"Number" = $(Get-Random -Minimum 100 -Maximum 200 ) }
}

Yes, sure… But! Since it’s a cloud operation against Microsoft 365 – you will be throttled if you start more than 2 parallel threads! Using just 2 threads does not provide significant performance improvements.

Batching

So, try PnP.PowerShell batches instead. When you use batching, number of requests to the server are much lower. Consider something like:

$batch = New-PnPBatch
1..100 | ForEach-Object{ Add-PnPListItem -List "ItemTest" -Values @{"Title"="Test Item Batched $_"} -Batch $batch }
Invoke-PnPBatch -Batch $batch

Measurements

Adding and setting 100 items with “Add-PnPListItem” and “Set-PnPListItem” in a large (more than 5000 items ) SharePoint list measurements:

	Add-PnPListItem Time per item, seconds	Set-PnPListItem Time per item, seconds
Regular, without batching	1.26	1.55
Using batches (New-PnPBatch)	0.10	0.80
Using “Parallel” option, with ThrottleLimit 2	0.69	0.79
Using “Parallel” option, with ThrottleLimit 3	0.44 (fails level: ~4/100)	0.53 (fails level: ~3/100)

Adding items with PnP.PowerShell batching is much faster than without batching.

Vlad Software Engineer

Microsoft 365 SharePoint, Teams, PowerShell, Azure, Search, Governance, Automation etc.