PowerShell script to extract time statistics from a recently installed feature update (full OS swap)

Get-FeatureUpdatesTimeStatistics.ps1

## Get time statistics for a Windows feature update (full OS swap)
# Requires that the "Windows.old" folder still exists on the machine

#Requires -RunAsAdministrator 

# Specify the FU version
$FUVersion = "24H2"
$BuildNumber = "26100"

# Check we are on the correct build
$CurrentBuildNumber = Get-CimInstance Win32_OperatingSystem | Select -ExpandProperty BuildNumber
if ($CurrentBuildNumber -ne $BuildNumber) 
{
    Write-Host "Not on build $BuildNumber. Exiting..."
    Exit 0
}

# Check if Windows.old exists
if (-not (Test-Path "C:\Windows.old\Windows\System32\winevt\Logs\System.evtx") )
{
    Write-Host "Windows.old does not exist. Exiting..."
    Exit 0
}

# Get the latest restart event before new OS files swap
$Params = @{
    Path = "C:\Windows.old\Windows\System32\winevt\Logs\System.evtx"
    Id = 1074
}
$PostInstallRebootTime = Get-WinEvent -FilterHashtable $Params -ErrorAction SilentlyContinue | 
    Select -First 1 |
    Select -ExpandProperty TimeCreated

# Get Windows update events prior to reboot
$Params = @{
    Path = "C:\Windows.old\Windows\System32\winevt\Logs\System.evtx"
    ProviderName = "Microsoft-Windows-WindowsUpdateClient"
}
$WUEvents = Get-WinEvent -FilterHashtable $Params -ErrorAction SilentlyContinue

# Find upgrade start time
$UpgradeStartTime = $WUEvents | 
    Where-Object { $_.Id -eq 43 -and $_.Message -match "11," -and $_.Message -match "$FUVersion" } | 
    Select -First 1 | Select -ExpandProperty TimeCreated

# Find download start time
$DownloadStartTime = $WUEvents | 
    Where-Object { $_.Id -eq 44 -and [datetime]$_.TimeCreated -lt $UpgradeStartTime } | 
    Select -First 1 | Select -ExpandProperty TimeCreated

# Find commit start time
$CommitStartTime = $WUEvents | 
    Where-Object { $_.Id -eq 218 -and $_.Message -match "11," -and $_.Message -match "$FUVersion" } | 
    Select -First 1 | Select -ExpandProperty TimeCreated

# Find commit finish time
$CommitFinishTime = $WUEvents | 
    Where-Object { $_.Id -eq 216 -and $_.Message -match "11," -and $_.Message -match "$FUVersion" } | 
    Select -First 1 | Select -ExpandProperty TimeCreated

# Find Upgrade finish time
$Params = @{
    LogName = "System"
    ProviderName = "Microsoft-Windows-WindowsUpdateClient"
    Id = 19
}
$UpgradeFinishTime = Get-WinEvent -FilterHashtable $Params -ErrorAction SilentlyContinue | 
    Where-Object { $_.Message -match "11," -and $_.Message -match "$FUVersion" -and $_.Message -notmatch "KB" } |
    Select -First 1 | Select -ExpandProperty TimeCreated

# Calculate durations
# Total upgrade duration (ie time between upgrade start, reboot and finish)
If ($UpgradeStartTime -and $UpgradeFinishTime)
{
    $TotalUpgradeDurationMinutes = ($UpgradeFinishTime - $UpgradeStartTime).TotalMinutes
}

# Install duration - this value is only accurate if the device was rebooted immediately after the upgrade
#if ($UpgradeStartTime -and $PostInstallRebootTime)
#{
#    $InstallDurationMinutes = ($PostInstallRebootTime - $UpgradeStartTime).TotalMinutes
#}

# Content download duration
If ($DownloadStartTime -and $UpgradeStartTime)
{
    $DownloadDurationMinutes = ($UpgradeStartTime - $DownloadStartTime).TotalMinutes
}

# Commit duration
If ($CommitStartTime -and $CommitFinishTime)
{
    $CommitDurationMinutes = ($CommitFinishTime - $CommitStartTime).TotalMinutes
}

# Offline time, ie time between post-install reboot and upgrade finish
If ($PostInstallRebootTime -and $UpgradeFinishTime)
{
    $OfflineTimeMinutes = ($UpgradeFinishTime - $PostInstallRebootTime).TotalMinutes
}

# Output results
[PSCustomObject]@{
    DownloadStartTime = $DownloadStartTime
    UpgradeStartTime = $UpgradeStartTime
    PostInstallRebootTime = $PostInstallRebootTime
    CommitStartTime = $CommitStartTime
    CommitFinishTime = $CommitFinishTime 
    UpgradeFinishTime = $UpgradeFinishTime  
    DownloadDurationMinutes = $DownloadDurationMinutes
    #InstallDurationMinutes = $InstallDurationMinutes
    CommitDurationMinutes = $CommitDurationMinutes
    OfflineTimeMinutes = $OfflineTimeMinutes
    TotalUpgradeDurationMinutes = $TotalUpgradeDurationMinutes
}