# Capacity Planning Guide

Plan and scale infrastructure to meet demand.

## Capacity Assessment

Evaluate current resource utilization:

```bash
#!/usr/bin/env nu

def assess-capacity [] {
  let metrics = {
    cpu_usage = (provisioning metrics get "cpu_utilization_percent" --aggregate avg),
    memory_usage = (provisioning metrics get "memory_utilization_percent" --aggregate avg),
    disk_usage = (provisioning metrics get "disk_utilization_percent" --aggregate avg),
    network_throughput = (provisioning metrics get "network_bytes_per_second" --aggregate max),
    request_rate = (provisioning metrics get "http_requests_per_second" --aggregate max)
  }

  print $metrics

  # Calculate utilization headroom
  let headroom = {
    cpu = (100 - $metrics.cpu_usage),
    memory = (100 - $metrics.memory_usage),
    disk = (100 - $metrics.disk_usage)
  }

  print $"Headroom: ($headroom)"
}
```

## Growth Projections

Project future capacity needs:

```nickel
{
  capacity_planning = {
    # Current baseline
    current = {
      users = 10000,
      requests_per_second = 1000,
      storage_gb = 500
    },

    # Growth factors
    growth = {
      monthly_user_growth = 0.10,  # 10% per month
      peak_traffic_factor = 2.5,    # Peak is 2.5x baseline
      storage_growth = 0.05          # 5% monthly
    },

    # Projections
    projections = [
      { month: 1, users: 11000, rps: 1100, storage_gb: 525 },
      { month: 3, users: 13310, rps: 1331, storage_gb: 580 },
      { month: 6, users: 17716, rps: 1772, storage_gb: 640 },
      { month: 12, users: 31384, rps: 3138, storage_gb: 805 }
    ]
  }
}
```

## Scaling Triggers

```nickel
{
  auto_scaling = {
    triggers = [
      {
        metric = "cpu_utilization",
        threshold_up = 75,
        threshold_down = 25,
        scale_up_by = 2,
        scale_down_by = 0.5
      },
      {
        metric = "memory_utilization",
        threshold_up = 80,
        threshold_down = 30,
        scale_up_by = 1.5
      },
      {
        metric = "request_queue_depth",
        threshold_up = 100,
        threshold_down = 10,
        scale_up_by = 3
      }
    ]
  }
}
```

## Related Documentation

- [Auto-Scaling](../examples/cost-optimization-examples.md)
- [Monitoring](./monitoring.md)
- [Performance Tuning](../development/build-system.md)
