But the stack will be used for each request, especially in Java app servers where stacks are often dozens of frames deep. The lowest stack size I could get away

But the stack will be used for each request, especially in Java app servers where stacks are often dozens of frames deep. The lowest stack size I could get away with for Tomcat 6/JDK 1.6 was 128 KB. Sure, you could do better with a lightweight C/C++ solution.