Small memory footprint web servers?


For a web services POC using Spring + CXF I am testing Jetty in a OS environment which has limited resources (such as total RAM of 512 MB), runs a .Net application and has to run a Java servlet container.


At present Jetty has the following JVM parameters:

 -Xms15M -Xmx15M -XX:MaxPermSize=16M and the Xss (stack size per thread) is the default.


While load testing with ab (Apache benchmark), I was able to lower the heap size to 15MB however the perm zise can not be lowered to  less than 16MB. 

The scenario tested was with 50,000 requests over 10 threads, the size of each request is 10k. 



Has anyone had any good experience with other small memory footprint web server? I used Winston before for running hudson, but is it being utilized in production environments?