> > I'm not sure this is the same issue. Look at this test code:
> For reasons I don't fully understand, this code doesn't seem to do
> anything.  A print statement after the Unix.openfile is never printed.

Possibly you use print_string or something like this. Such output is
cached. You should either flush stdout or use print_endline.

> > let read_data _ =
> > 	let fd = Unix.openfile "/dev/random" [] 0o644 in
> You probably want to use something like /dev/urandom or /dev/zero
> here.

I'm so sleepy at this time, it's a quick written test code :-) RSS still
grows after I changed the source of data to /dev/zero. I didn't expect
something else...