In java, the jvm is the OS. Every object in Java is allocated in the heap, and doesn't provide developers direct control of a more optimized way of allocating o

In java, the jvm is the OS. Every object in Java is allocated in the heap, and doesn't provide developers direct control of a more optimized way of allocating objects. In rust, you can specify an object to be on the stack or on the heap, rust compiler is very smart and it knows where an object goes out of scope, thus not needed anymore and insert a code on that location to drop that object and free memory. Unlike in Java, which waits for the garbage collector to drop objects. In a nutshell, java engineering effort is directed into the jvm(jit) to provide high performance when the applications are run. Rust engineering, on the other hand is directed on the compiler figuring out where and when an object is out of scope, no matter how complex it was attached to other objects, passed around multiple functions. It will figure it out.