Got you covered. https://github.com/jart/cosmopolitan/blob/master/examples/rusage.c https://github.com/jart/cosmopolitan/blob/master/examples/ru... $ git c

Got you covered. https://github.com/jart/cosmopolitan/blob/master/examples/rusage.c https://github.com/jart/cosmopolitan/blob/master/examples/ru... $ git clone https://github.com/jart/cosmopolitan && cd cosmopolitan $ make -j8 o//examples/rusage.com o//examples/hello.com $ o//examples/rusage.com o//examples/hello.com hello world 123 RL: took 90µs wall time RL: ballooned to 108kb in size RL: needed 106µs cpu (0% kernel) RL: caused 13 page faults (100% memcpy) This one has a tiny bit more overhead than the practical minimum you saw earlier in the benchmark. Note that APE binaries start off as shell scripts so the first run is going to be slower. It's something I'm working towards improving in a variety of ways. Here's the executive summary of the upcoming changes: int ws, pid; CHECK_NE(-1, (pid = fork())); if (!pid) { execve("ape.com", (char *const[]){"ape.com", 0}, environ); perror("execve"); _Exit(127); } CHECK_EQ(pid, wait(&ws)); CHECK_TRUE(WIFEXITED(ws)); CHECK_EQ(0, WEXITSTATUS(ws)); Here's the latency of the various execution strategies: FORK+EXEC+EXIT+WAIT │ APE │ APE-LOADER │ BINFMT_MISC ─────────────────────────────────────────────────────────────── fork() + execve() │ 55µs │ 66µs │ 56µs vfork() + execve() │ 25µs │ 446µs │ 35µs /bin/sh -c ./ape (1st) │ 485µs │ 457µs │ 170µs /bin/sh -c ./ape (avg) │ 148µs │ 466µs │ 159µs