# Cleanup Windows

Schedule retention cleanup during specific time windows.

## Overview

Cleanup windows allow you to run retention policy cleanup during off-peak hours (e.g., 2-6 AM UTC) to minimize impact on production workloads.

## Configuration

```csharp
builder.Services.AddPostgresRetentionPolicies(options =>
{
    options.Enabled = true;
    options.CleanupInterval = TimeSpan.FromHours(1);
    options.UseCleanupWindow = true;
    options.CleanupWindowStart = TimeSpan.FromHours(2);   // 2 AM UTC
    options.CleanupWindowEnd = TimeSpan.FromHours(6);     // 6 AM UTC
});
```

## Cleanup Window Logic

```csharp
private bool IsWithinCleanupWindow()
{
    if (!_options.UseCleanupWindow)
        return true;  // Always run if window disabled

    var now = DateTime.UtcNow.TimeOfDay;
    var start = _options.CleanupWindowStart;
    var end = _options.CleanupWindowEnd;

    if (start < end)
    {
        // Normal window (e.g., 2 AM to 6 AM)
        return now >= start && now < end;
    }
    else
    {
        // Window crosses midnight (e.g., 10 PM to 2 AM)
        return now >= start || now < end;
    }
}
```

## Examples

### Off-Peak Hours (2-6 AM UTC)

```csharp
options.CleanupWindowStart = TimeSpan.FromHours(2);   // 2 AM
options.CleanupWindowEnd = TimeSpan.FromHours(6);     // 6 AM
```

### Night Window Crossing Midnight

```csharp
options.CleanupWindowStart = TimeSpan.FromHours(22);  // 10 PM
options.CleanupWindowEnd = TimeSpan.FromHours(4);     // 4 AM
```

### Weekend Only

For weekend-only cleanup, implement custom logic:

```csharp
protected override async Task ExecuteAsync(CancellationToken ct)
{
    while (!ct.IsCancellationRequested)
    {
        if (DateTime.UtcNow.DayOfWeek is DayOfWeek.Saturday or DayOfWeek.Sunday)
        {
            await RunCleanupAsync();
        }

        await Task.Delay(TimeSpan.FromHours(1), ct);
    }
}
```

## See Also

- [Retention Policies Overview](README.md)
- [Time-Based Retention](time-based-retention.md)
- [Size-Based Retention](size-based-retention.md)