Is it possible to optimize the stack for memory so that there is no x2 consumption?

In Java, each thread's stack is allocated with a fixed size, which by default can be quite large, and the JVM doubles the stack size if necessary, leading to increased memory consumption.

Memory optimization of the stack can be achieved through:

• Configuring the stack size at JVM startup using the -Xss parameter. Reducing the stack size will decrease memory usage, but a too small size may lead to a StackOverflowError.

• Using more efficient algorithms and data structures to reduce recursion depth and the number of calls, thereby decreasing stack load.

• Profiling and analyzing the stack to identify redundant calls and optimize the code.

Example of starting JVM with a reduced stack size:

java -Xss256k -jar yourapp.jar

Thus, there is no direct way to prevent stack doubling, but you can control the size and optimize your code to reduce memory consumption.