[erlang-questions] erlang:now() vs os:timestamp()

[Manuel A. Rubio "Bombadil"]

Hi,

I saw a keynote[1] from Rick Reed (WhatsApp) and he said: "Prefer 
os:timestamp to erlang:now"... I did a benchmark to test it[2], and get 
the following results:

os:timestamp =  1.44  1.38  1.38
erlang:now   =  1.01  1.00  1.00

I know that he says "prefer" and not "better"... but the benchmark says 
that he should be say the opposite :-P

What do you think?

[1] 
http://www.erlang-factory.com/upload/presentations/558/efsf2012-whatsapp-scaling.pdf
[2] https://gist.github.com/manuel-rubio/5302361

Regards.
Manuel Rubio.