How?
vfork is not available from perl.
And anyway, the manual page for the syscall (on Linux) says:
The vfork() function has the same effect as fork(), except that the behaviour is undefined if the process created by vfork() either modifies any data other than a variable of type pid_t used to store the return value from vfork(), or returns from the function in which vfork() was called, or calls any other function before successfully calling _exit() or one of the exec() family of functions.
It doesn't look like a good option!!!