The Making of Energy Efficient Datacenters
The Crooked E: The Unshredded Truth About Enron is a wonderful movie to watch. It is based on the book, The anatomy of greed, written by a former employee of Enron, Brian Cruver. One interesting thing that comes on our minds is the size of all power companies. They are all huge. We all depend on power for just about everything and yet very rarely do we think about conserving energy. A typical PC for example takes about 135 watts of power. A data center with about a 1000 servers should typically take about 135 x 1000 Watts or 135 Kilowatts and that would just power the computers. This does not include the air-conditioning and lighting. According to to a research paper sponsored by The California Energy Commission in a datacenter about 50% of the total energy consumed is by the servers and
about 35% is the air conditioners.
Here are some interesting research done in this field -
Feeling the heat- An interesting paper by Liebert describing the challenge
of effectively managing the heat dissipation in datacenters.
Heat-Density Trends in Data Processing, Computer Systems, and Telecommunications
Equipment- This white paper provides valuable
current data and best available insights regarding historical and
projected trends in power consumption and the resulting heat
dissipation in computer and data processing systems (servers and
workstations), storage systems, and central office-type
telecommunications equipment.
This problem can be solved by making better energy efficient air
conditioners and by making more energy
efficient computers. Many companies have taken a lot of interest
in subject. However, nothing substantial has been done primarily
because of the market requirements. The end users still want to host
their sites on the fastest processors which drives the market with the
latest processors. Going at this rate we would reach a time soon when
the energy required would be much higher than the energy available in
the market.
Intel, AMD, Transmeta and Via have all released processors which
consume very low power. A typical Pentium or AMD processor consumes
about 25 Watts of power, whereas these low powered processors take only
about 5 watts of power i.e. about 5 low powered processors would
consume as much power as a single main stream processor of today. These
low powered processors are also generally fan less processors which
means lower noise levels too. Intel has the centrino which has a lower
power consumption than the regular pentiums. Intel also has the arm
processors but those are RISC. Our prime focus would be AMD, Transmeta
and Via. They all have some very promising products.
One thing to be noted is that most of these low powered processors work
only at about 1.2GHz or lower. So they won't be as fast the pentium4s.
Which means one would have to host lesser sites per server. A good
recommendation would be upto a maximum of 600 sites on a
regular pentium 4 server. A low powered processor should comfortably
take about 200 sites. One advantage of these low powered processors is
that they have a very small form factor too. This means that one can
have more such servers in the same space that is typically allocated to
a high powered servers. All datacenters use a profitability matrix
based on the following rule: Performance/Per
Watt/Per Cubic Foot. This is one place where the low powered
processors really score high.
AMD Geode