> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ditto.live/llms.txt
> Use this file to discover all available pages before exploring further.

# SDK Logging

> Learn how to configure and use the logging system in the Ditto SDK for monitoring and debugging your applications.

Ditto provides comprehensive logging capabilities to help you monitor, debug, and optimize your applications. The SDK includes a sophisticated logging system with automatic rotation, compression, and configurable retention policies.

## Logging Rotation in Ditto

### Core System

Ditto uses a custom `ditto-rotating-file` crate that provides thread-safe rotating file writers with automatic compression.

### Rotation Triggers

Files rotate based on two criteria:

* **Size limit**: Default 1MB uncompressed (configurable 1MB-1GB)
* **Age limit**: Default 24 hours (configurable 1+ hours)

### File Management

* **Naming**: `ditto-logs-YYYY-MM-DD-HH-MM-SS.microseconds.log`
* **Compression**: Automatic gzip compression when rotated (`.log` → `.log.gz`)
* **Retention**: Default 15 files maximum (configurable 3-64 files)

## Configuration Parameters

| Parameter                             | Default | Range      | Description               |
| ------------------------------------- | ------- | ---------- | ------------------------- |
| `rotating_log_file_max_size_mb`       | 1MB     | 1MB-1GB    | Size trigger for rotation |
| `rotating_log_file_max_age_h`         | 24      | 1+ hours   | Age trigger for rotation  |
| `rotating_log_file_max_files_on_disk` | 15      | 3-64 files | Maximum files to retain   |

## Key Features

* **Multi-threaded compression** in background
* **Automatic cleanup** of oldest files when limit exceeded
* **Runtime reconfiguration** without restart
* **Export functionality** for diagnostics
* **Crash recovery** - compresses leftover uncompressed files on startup

## Integration

* Uses `tracing-subscriber` with JSON formatting
* Always logs at **DEBUG level** to disk (independent of console level)
* Filtered to prevent recursive logging from the rotation system itself

## Disk Usage

The system maintains approximately **\~15MB disk usage** by default (15 × 1MB compressed files) and handles rotation completely automatically with robust error recovery.

## Related Documentation

* For debugging specific issues, see [Troubleshooting](/sdk/latest/deployment/troubleshooting)
* For remote log collection, see [Device Observability](/sdk/latest/deployment/device-observability-and-ditto-logs/)