Log Viewer

The Log Viewer is a diagnostic tool in KOS Studio that allows you to view and analyze logs from connected devices or images. This tool is essential for troubleshooting and monitoring device activity during development and testing.

Key Features

  • Multiple Log Types: Access any log file from the device’s /mnt/datafs/logs/live folder to get comprehensive insight into device behavior and quickly identify issues across different system layers
  • Real-Time Monitoring: See log entries as they happen, enabling immediate detection of errors and issues during development and testing
  • Multiple Instances: Monitor different log types side-by-side for faster correlation of issues and more efficient troubleshooting
  • Mini Map Navigation: Quickly scan through large log files and jump directly to errors or stack traces, saving time when analyzing extensive logs
  • Customizable Themes: Apply different colors to multiple windows for instant visual identification, reducing confusion when working with several log viewers simultaneously
  • Offline Support: Continue analyzing logs even when disconnected from the Studio server, ensuring uninterrupted troubleshooting sessions
  • Automatic Queue Management: Focus on recent activity without manual cleanup—the tool automatically maintains the most recent 10MB of logs
  • Persistent Settings: Your window names and themes are preserved when reconnecting, maintaining your organized workspace

Accessing the Log Viewer

Opening the Tool

  1. Log into the KOS studio.
  2. Once logged in, KOS Studio displays my images and connection manager windows.
  3. Select the running image/device from the connection manager window to start a tool.
  4. Find the Active Tools section
  5. Click + Start New Tool
  6. Select Log Viewer from the dropdown menu
  7. Choose the log file you want to view from the available files in /mnt/datafs/logs/live

Working with Multiple Log Viewers

You can open multiple Log Viewer instances for the same running image, which is useful for monitoring different log files simultaneously.

Managing Multiple Instances

  • Each instance can be renamed individually to help you distinguish between them
  • Custom names and theme selections are preserved when you replay an image after it becomes inactive
  • All previously opened Log Viewer instances will automatically reopen when you reconnect

Viewing Logs

Log Display

When connected, the Log Viewer displays log entries in real-time:

  • New log entries appear automatically at the end of the screen
  • The display scrolls to show the most recent entries
  • Log colors adapt to your selected theme for better readability

Log Queue Management

The Log Viewer maintains a queue with a 10MB limit. When this limit is reached:

  • Older log entries are automatically removed to make room for new ones
  • The most recent logs are always preserved
  • This ensures optimal performance while maintaining recent diagnostic information

Switching Between Log Files

The Log Viewer allows you to switch between different log files from the /mnt/datafs/logs/live folder. Common log files include:

  • Java Logs – Application-level Java logging information
  • UI Logs – User interface event logs
  • System Logs – Operating system and system-level logs
  • Boot Logs – Device startup and initialization logs

How to Switch Log Files

  1. Locate the Log Type menu (collapsible/expandable)
  2. Click to expand the menu
  3. Select your desired log file from the available options
  4. The display updates immediately to show the selected log file
  5. The menu automatically collapses after selection

Mini Map Feature

The Mini Map provides a bird’s-eye view of the entire log file, making it easy to navigate large log files and quickly locate areas of interest like stack traces and error messages.

Using the Mini Map

  • The Mini Map appears on the side of the log display without obstructing the main view
  • Click on any area of the Mini Map to jump directly to that location in the logs
  • Vertical scrolling in the main log display is reflected in the Mini Map
  • Horizontal scrolling does not affect the Mini Map view
  • The Mini Map theme matches your selected log viewer theme for consistency

Customizing Themes

The Log Viewer offers six color themes to help you visually distinguish between multiple windows or match your viewing preferences.

Available Themes

  1. Light
  2. Dark
  3. Aqua
  4. Grass
  5. Red Sands
  6. Ocean

Applying a Theme

  1. Locate the Theme menu (collapsible/expandable)
  2. Click to expand the menu
  3. Select your desired theme
  4. The theme applies immediately to the entire window, including the Mini Map
  5. The menu automatically collapses after selection

Tip: Use different themes for multiple Log Viewer instances to quickly identify which window you’re working with.

Quick Tips

  • Rename your Log Viewers when using multiple instances to avoid confusion
  • Use the Mini Map to quickly scan for errors or stack traces in large log files
  • Apply different themes to multiple Log Viewer windows for easier identification
  • Monitor the 10MB queue limit – if you need historical logs, consider capturing them before they’re rotated out
  • Keep connections active to ensure continuous log monitoring