I'd like to time some funcs implemented in an extension but they are
really fast so:

start = Time.now
my_ext_function(args)
elapsed_time = Time.now - start

will not do (resolution is microsecs?). The obvious way is to repeat the
call a large number of times and then take an average but I wonder if
there is any other way to time (really) short time intervals?
(Platform-specific syscalls not allowed!)

Thanks in advance,

Robert