erlang:now issues when generating ids

Problem stems from the fact that "guaranteed that subsequent calls to this BIF returns continuously increasing values"; see also https://github.com/erlang/otp/blob/master/erts/emulator/beam/erl_time_sup.c#L849
Hence

1. "Sequence counter" id field will never go higher than 1000, wasting precious 6 bits.
2. Generating more than 10e6 ids per second in one erlang wm will cause skewness of "time" id field, possibly resulting in incorrect ordering of ids from different machines; incomparability margin of these ids could grow uncontrollably.

Solution
Simply replacing erlang:now with os:timestamp seems to be enough.