Demo for effective time prediction in progress in PowerShell

progressPrediction.ps1

$queries = 0..25
Set-Variable -Name SecondsPerQuery -Value 11 -Option ReadOnly -Force
Set-Variable -Name Variability -Value 0.07 -Option ReadOnly -Force
$queries | ForEach-Object -Begin {
    $averageSecondsPerQuery = $SecondsPerQuery  # Average seconds per query will be used to predict the time per iteration
} -Process {
    $index = $_
    $timing = [timespan]::FromSeconds((Get-Random -Minimum ((1.00 - $Variability) * $SecondsPerQuery) -Maximum ((1.00 + $Variability) * $SecondsPerQuery)))
    $averageSecondsPerQuery = $averageSecondsPerQuery * ($index / $queries.Length) + $timing.TotalSeconds * ($queries.Length - $index) / $queries.Length
    [pscustomobject]@{
        Index                  = $index
        SecondsForIteration    = $timing.TotalSeconds
        AverageSecondsPerQuery = $averageSecondsPerQuery
        SecondsRemaining       = (($queries.Length - $index) * $averageSecondsPerQuery)  # A moving weighted average
    }
    Write-Progress -Activity 'Predicting timing' -SecondsRemaining (($queries.Length - $index) * $averageSecondsPerQuery) -Status "$index / $($queries.Length)" -PercentComplete (($index / $queries.Length) * 100) -CurrentOperation "Query $index of $($queries.Length)" -Id 0
    Start-Sleep -Seconds $timing.TotalSeconds  # Simulate query
} | Format-Table -AutoSize -Wrap
Write-Progress -Activity 'Predicting timing' -Status 'Complete' -Id 0 -Completed