1.
Cloud computing is...

2.
...a huge phenomenon• More than 3 million data centers of widely varying sizes worldwide (IDC)• US government datacentres - up from 432 in 1998 to 2,094 in 2010

3.
... driven by• Massive expansion in data• 1.8 trillion gigabytes of digital information created globally last year• 75% of that generated by individuals, not corporations• But corporate use also huge -- e.g. NYSE generates 2,000 GB/day, which has to be stored for years

4.
... power-hungry• In US, cloud computing used 76 billion kilowatt-hours of electricity in 2010• That’s ~ 2 percent of all electricity used in the US that year (Jonathan Koomey, Stanford)• Compare with paper industry, which took 67 billion kilowatt-hours from the grid in 2010

5.
(just for comparison)• One data-centre = one medium-sized town• Google consumes 300 megawatts (MW)• Facebook 60m MW

6.
... very inefficient• Typically data-centres only use 6-12% of energy for actual computation • In one sample of 333 servers monitored in 2010, >50% were found to be comatose (i.e. not doing any computation) • Nearly 75% of servers in the sample were using less than 10 percent of their computational power

7.
... wasteful• Low utilization rates mean that the energy wasted is as much as 30 times the amount of electricity used to carry out the basic purpose of the data centre• Most of the energy goes on keeping idle machines running, and cooling them down

8.
... polluting• Data-centres use (diesel generators for backup• These often violate air pollution regulations • (~ 12 data-centres in Virginia and Illinois fined in one year)

9.
... badly managed• Most run at max capacity 24x7x365 • (because of fear of downtime)• Waste 90% of the energy they pull off the grid

10.
... in a word, nuts• On both financial and environmental grounds.

11.
Based on James Glanz’s NYT article:http://www.nytimes.com/2012/09/23/technology/data-centers-waste-vast-amounts-of-energy-belying-industry-image.html

12.
John Naughton memex.naughtons.org