memory leak: Destroy function does not work

[ReverseSystem001]

when you add sleep(10) func and watch the gpu memory through: watch -n 1 nvidia-smi, you will find the engine and runtime destroy is not working.
sleep(10);
this->context->destroy(); // worked
sleep(10);
this->engine->destroy(); // not work
sleep(10);
this->runtime->destroy(); // not work