[clug] Re CO2 footprint of Searches: Storm in A Tea Cup or Deep Green Issue?

[Andrew Janke]

On Wed, Sep 9, 2009 at 10:20, Robert Edwards<bob at cs.anu.edu.au> wrote:
> I have been asking this same question for some years now but there
> doesn't appear to be a lot of research results into this area. How
> much does it _really_ cost in energy terms to get me a gigabyte of
> data from a data center in Iceland vs. one in Canberra?

Well having once plugged an ammeter in line with a HP2824 gigabit
switch and a few linksys equivalents (out of morbid curiosity) I can
say that the power usage when the switch was under "load" vs idle was
not measurable.  In this case load == lots and lots of NFS traffic
meaning lots of blinking flashing lights.

So perhaps the argument here about data transfer from Canada vs from
local is sort of akin to the public transport bus + train thing. So
long as the infrastructure is there, there is a negligible extra cost
for one more passenger on the train.

Now the cost to originally install all that infrastructure as compared
with plugging in a single Cat6 patch lead to your own data centre in
the next room is probably somewhat large! Meaning I would punt (but
have no real idea) that the cost of moving data about is predominately
to cover the initial cost of the equipment, undersea cables, floor
space, cooling etc. Does someone know how much extra power and A/C a
big-iron network switch/cabinet/room uses when under load as compared
to at idle?


--
Andrew Janke
(a.janke at gmail.com || http://a.janke.googlepages.com/)
Canberra->Australia    +61 (402) 700 883