ActiveDirectory PowerShell Module has scalability/performance issues.
The ActiveDirectory PowerShell Module has scalability/performance issues when querying hundreds of thousands of objects for more than a dozen properties and exporting that data to a Csv file.
When executing 'Get-ADUser -Filter * -Properties $Properties | Export-Csv' where $Properties contains ~20 properties and the $Object.Count is ~500,000, the report often takes ~180 minutes, even when querying a domain controller local to the source. Using JoeWare.net's ADFind, a lightweight and high performance C++ executable wrapped and invoked via PowerShell, the report takes less than 10 minutes.
Herbert Mauerer commented
ADWS also does nto scale well when many concurrent users issue queries.