Monitoring GDI Objects

A GDI Object (Graphics Device Interface) is a core Windows component responsible for rendering graphical objects and sending them to devices such as displays and printers. Every open window and application uses GDI objects.

The problem arises when too many objects are in use simultaneously. The maximum number of GDI objects allowed is 10,000. When this limit is exceeded, the display can become corrupted, or the program may freeze or crash.

You can monitor GDI objects either with Task Manager or with a free application specifically designed for GDI object monitoring. If monitoring is not possible with Task Manager for some reason, you can use a downloadable application from the internet. Detailed instructions for using such an application are provided below.

Monitoring with Task Manager

Task Manager → Select More details in the lower left corner → Go to the Details tab → Right-click the Status column header → Select Select columns → Check the box for GDI Objects.

Start G4 and monitor how the number of GDI objects behaves. When the maximum limit (10,000) is exceeded, the display may become corrupted, or the program may freeze or crash.

Monitoring with an Application

1. Download the free application for monitoring GDI objects from https://www.nirsoft.net/utils/gdi_handles.html

The download link is located at the bottom of the page — choose the version that matches your Windows installation (most commonly x64).

2. Extract the ZIP file you downloaded.

3. Launch both Vertex and the GDIView.exe application extracted from the ZIP file. The application does not require installation.

4. In the process list displayed by the GDIView application, locate the Vertex process. If it does not appear in the list, click the Refresh button in the top toolbar.

5. From the Options menu, select the update frequency for the results list. A recommended value is 1 or 2 seconds.

6. Arrange the Vertex and GDIView windows so that the title bar and the row for the Vertex process are visible in the GDIView application.

7. If a GDI object leak occurs, the "All GDI" and most likely the "Bitmap" counts will gradually start increasing. Record a screen capture video showing this situation. It doesn’t matter if the video is several hours long.