Technical Q&As


AMT_PE 10 - AMT_PE Application Crashes (1-Aug-95)


Q I have a variety of Macs, all with 8 MB of RAM installed. As I test my AMT/PE title, I notice that sometimes when it is playing a QuickTime movie, it stops and the application just sits there: the cursor can be moved but clicking on the mouse does nothing, and Command-Q doesn't work. As a result, I have to reboot the machine. This problem cannot always be reproduced, and happens at different points in the title. My title requires a partition of 4.5 MB and my System takes about 3 MB.

A The total of your System partition and your application's partition comes perilously close to your 8MB of RAM. QuickTime occasionally requests more memory (above and beyond what the System uses while it is idle). You can see this if you observe the System bar in the About this Macintosh dialog as you launch and run movies in MoviePlayer: it can grow in size by about 300K - 400K per movie open!) If this RAM is not available, the application will hang.

You need to make sure that you (and anyone who buys and runs your title) has enough RAM left over after launching the title for QuickTime to run happily. There is no exact science for determining this other than hooking up a second monitor to your machine and watching a memory-monitor utility like Swatch to see the worst-case size of the System (when you have the maximum number of movies playing at once). If you subtract this worst-case size from the size of the System when nothing else is running, you will get a rough estimate of how much "extra" space must be free in order for your app to run.

In lieu of checking at startup for this extra RAM, you should explicitly mention the need for it in your documentation.

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