Meant to tag Codename One iOS VM low level issues/capabilities and usage of ParparVM that isn't necessarily related to Codename One
ParparVM is an open source VM developed by Codename One to replace the defunct XMLVM with which it was originally built. It translates java bytecode to c source code that can be compiled on Apple's xcode.
ParparVM was designed as a client side VM and features a concurrent GC that doesn't block the current execution thread. In order to accomplish such concurrence a small penalty is paid during usage but this allows for smoother runtime.