Aggregate and IdentityNow Source with Disable Optimization. Associated blog post https://blog.darrenjrobinson.com/aggregating-sailpoint-identitynow-sources-via-api-with-powershell/

Aggregate Source without Optimization.ps1

# Your API Client ID
$clientID = 'yourClientID'
# Your API Client Secret
$clientSecret = 'yourSecret'
$Bytes = [System.Text.Encoding]::utf8.GetBytes("$($clientID):$($clientSecret)")
$encodedAuth = [Convert]::ToBase64String($Bytes)
# Your IdentityNow Tenant Name
$orgName = 'yourOrg'
# IdentityNow Admin User and PWD to connect with via oAuth
$adminUSR = [string]"yourAdminAccount".ToLower()
$adminPWDClear = 'yourAdminPWD'
# Encrypt creds from above. Requires the PSCX Module
$passwordHash = Get-Hash -Algorithm SHA256 -StringEncoding utf8 -InputObject ($($adminPWDClear) + (Get-Hash -Algorithm SHA256 -StringEncoding utf8 -InputObject ($adminUSR)).HashString.ToLower())
$adminPWD = $passwordHash.ToString().ToLower() 

# Base URI for Private API's (v1 APIs)  
$baseURI = "https://$($orgName).identitynow.com"
# URI to get Token 
$tokenURI = "https://$($orgName).identitynow.com/api/oauth/token?grant_type=password&username=$($adminUSR)&password=$($adminPWD)"
# Get Token
$token = Invoke-RestMethod -Method POST -Uri $tokenURI -Headers @{Authorization = "Basic $($encodedAuth)"} 
if ($token ) {
    try {
        # Private API Sources API
        $sourceID = 'sourceIDtoAggregate'
        $baseURI = "https://$($orgName).identitynow.com/api/source/loadAccounts/$($sourceID)"
        
        $headers = @{"Authorization" = "Bearer $($token.access_token)"}
        $aggregate = Invoke-RestMethod -Method POST -uri $baseURI -Headers $headers -Body "disableOptimization=true"  
        $aggregate.task     
    }
    catch {
        write-host -foregroundcolor yellow "Well, that didn't work. Are you referecing the correct Source and Org?"
    } 
}
else {
    write-host -foregroundcolor yellow "Well, that didn't work. Check your credentials, update and try again."
}