Monitoring graphics performance

Monitoring graphics memory consumption

You have two options for monitoring how much graphics memory a MIDlet consumes during runtime:

• Specify the Nokia-UI-Developer-Utils JAD attribute with the value GPUMem:

  Nokia-UI-Developer-Utils: GPUMem

  When the MIDlet is run, its graphics memory consumption is displayed on the device screen both in bytes and as a percentage of the total available memory. The displayed information includes:

  • The amount of free graphics memory on the device

  • The amount of shared memory used by the application (MIDlet) process

  • The amount of private memory used by the application (MIDlet) process

• In the MIDlet, retrieve the value of one of the com.nokia.gpu.memory system properties:

  • com.nokia.gpu.memory.total returns the total amount of graphics memory available on the device in bytes.

  • com.nokia.gpu.memory.used returns the amount of allocated graphics memory on the device in bytes.

  • com.nokia.gpu.memory.shared returns the amount of shared memory used by the application (MIDlet) process in bytes.

  • com.nokia.gpu.memory.private returns the amount of private memory used by the application (MIDlet) process in bytes.

  The following code snippet shows how to use the com.nokia.gpu.memory system properties to display a MIDlet's graphics memory consumption on the device screen.

  class MyCanvas extends Canvas {
  
      // ...
  
      protected void drawGpuMem(Graphics g) {
          g.setFont(font);
          int xMargin = 5;
          int yMargin = getHeight() - 5;
          String str = System.getProperty("com.nokia.gpu.memory.private");
          g.drawString("Private: " + (str != null ? str : "---"), xMargin, yMargin, Graphics.BOTTOM | Graphics.LEFT);
          yMargin -= fontHeight;
          str = System.getProperty("com.nokia.gpu.memory.shared");
          g.drawString("Shared: " + (str != null ? str : "---"), xMargin, yMargin, Graphics.BOTTOM | Graphics.LEFT);
          yMargin -= fontHeight;
          str = System.getProperty("com.nokia.gpu.memory.used");
          g.drawString("Used: " + (str != null ? str : "---"), xMargin, yMargin, Graphics.BOTTOM | Graphics.LEFT);
          yMargin -= fontHeight;
          str = System.getProperty("com.nokia.gpu.memory.total");
          g.drawString("Total: " + (str != null ? str : "---"), xMargin, yMargin, Graphics.BOTTOM | Graphics.LEFT);
      }
  
      protected void paint(Graphics g) {
          // ...
          drawGpuMem(g);
      }
  
  }

The following figure shows a MIDlet that uses the Nokia-UI-Developer-Utils JAD attribute to display its graphics memory consumption (top left). The MIDlet also uses the com.nokia.gpu.memory system properties to retrieve and display information about its graphics memory consumption (bottom).

Figure: Graphics memory consumption displayed on the device screen

Highlighting 2D elements when mixing 2D and 3D graphics

When mixing 2D and 3D graphics in a MIDlet, for example, when rendering Graphics content over an M3G scene, you can achieve the best performance by rendering the 2D graphics to the smallest possible areas of the underlying Canvas. The smaller and fewer the Canvas areas where you render 2D graphics, the better the graphics performance of the MIDlet.

Java Runtime for Symbian allows you to automatically highlight 2D graphics rendered over 3D graphics. By studying the highlighted 2D elements, you can determine which ones you need and which ones you can remove, and which ones you can make smaller and by how much. To highlight 2D graphics rendering in a MIDlet, specify the Nokia-UI-Developer-Utils JAD attribute with the value 2DBorders:

Nokia-UI-Developer-Utils: 2DBorders

When the MIDlet is run, 2D graphics rendered over 3D graphics are highlighted by borders drawn around the 2D elements. The 2D elements are identified and the borders drawn based on the quadtree algorithm.

The following figure shows a MIDlet that uses the Nokia-UI-Developer-Utils JAD attribute to highlight 2D elements rendered over 3D content.

Figure: Highlighted 2D elements rendered over 3D content

Measuring frame rate per seconds

To measure frame rate per seconds for a MIDlet, specify the Nokia-UI-Developer-Utils JAD attribute with the value FrameRate:

Nokia-UI-Developer-Utils: FrameRate

When the MIDlet is run, its frame rate per seconds is displayed on the device screen (see the preceding figures).

Example JAD file

Here is an example JAD file of a MIDlet that uses all the above means of monitoring graphics performance:

MIDlet-1: GpuMem,,GpuMem
MIDlet-Jar-Size: 6244
MIDlet-Jar-URL: GpuMem.jar
MIDlet-Name: GpuMem MIDlet Suite
MIDlet-Vendor: Nokia Corporation
MIDlet-Version: 1.0.0
MicroEdition-Configuration: CLDC-1.1
MicroEdition-Profile: MIDP-2.1
Nokia-UI-Developer-Utils: FrameRate, GPUMem, 2DBorders