An HTML page uses JavaScript to load a Java applet on Netscape 7.0/Solaris. The webpage loads the applet and then proceeds to exhibit a memory leak which eventually (10-20 hours+) hangs the system.

Customer is complaining about the memory leak problem when running java applets that communicate with the java script. Customer mentioned that he is seeing this memory leak problem when using java plugin 1.4.2_02 with netscape browser 7.0 and he does not see the problem with IE 5.5.

When memory does get eaten up, it follows a saw-tooth pattern: More memory is allocated. The amount of free memory is a decreasing percentage of available memory. When the amount of free memory hits a floor, it jumps back up to a percentage of available memory. In general, when it jumps back up, it jumps to a lower level than it did in the previous jump (e.g., if it had 50% memory free in jump 1, in jump 2, it might only have 47% free). This pattern continues until more memory has to be allocated. In customers testing, they saw 3520K of memory allocated initially. This grew to 4400K in approximately 10-15 minutes. When I stopped testing after approximately 3 hours, it had grown to 13544K.

Customer has considered several work arounds, such as calling the applet's method from within the applet. When they have done this test, they did not see the memory leak.
However, this work around is not acceptable from their application's architectural point of view. They have an architecture that uses the JavaScript - Java communication widely deployed.
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