Demand for ever-greater computing capacity is leading to
spiralling - and costly - power consumption. Danny Bradbury looks
at the best ways to cut costs and boost efficiency
Speak to most IT managers about power consumption and they will
give you a blank look. After all, it is generally the facilities
department that pays the energy bill. But electricity is becoming
an increasingly visible issue for IT departments. One way or
another, they are being forced to deal with it.
There are three main drivers for reducing power consumption:
environmental, financial and performance-related. In the
datacentre, performance is a critical factor, says Brent Kirby,
product marketing manager for Opteron processors at chip maker AMD.
"The noise we keep hearing from customers is that datacentres are
having problems increasing computing capability within the confines
of their power and cooling capabilities."
As companies try to squeeze more performance from their
computing infrastructures, they run into density and electricity
issues. Many server rooms were built at a time when people didn't
envisage packing as many servers into a small space as they do now.
Simply getting the electricity to power such dense computing
platforms into the server room is difficult enough. Then there is
the air conditioning, which also requires a significant amount of
energy, says Tikiri Wanduragala, EMEA eServer and storage
consultant at IBM.
One way around the problem is to switch from traditional
rack-based servers to blade servers, says Wanduragala, because
blades integrate components such as switching, fans and storage,
cutting down on consumption.
"What you can do is virtualise it and reduce power by spreading
the load over more CPUs," says Wanduragala. Running an application
across multiple servers within a blade chassis, you can make each
processor work less. That may be inefficient from a processing
perspective, but it reduces the power each processor consumes and
therefore the heat it emits, while still keeping your computing
density relatively high.
But what processors will go on those blades? Chip designers are
finally starting to realise the importance of power consumption
within the processor itself. Transmeta was one of the first to
drive this point home with its Crusoe and Efficeon processors, but
others have taken up the gauntlet. AMD has released low-power
versions of its Opteron processor, and also has a technology called
Powernow, which steps down the power consumption based on
application performance needs.
Intel has its own focus on power consumption at the processor
level. It previously focused on the issue only in its mobile
Centrino line, but has vowed to address it at desktop and server
level when it ships its next-generation microarchitecture next
year. This will merge its Netburst processor platform with the
Banias platform which underpinned the Pentium M, lauded as a mobile
processor designed to limit power consumption.
The other big development, which most processor designers of any
note are embracing, is multicore processing, in which more than one
processor core is put onto a piece of silicon to divide up the work
of multithreaded applications on the server, while making the
multitasking of single-threaded applications more effective on the
desktop.
"We are getting nearly twice the computing power within the same
thermal envelope as our single-core part," says AMD's Kirby. "We
did not have to increase the ceiling of our parts for our dual-core
chips to exist."
The other way to reduce datacentre power consumption is by using
virtualisation software to cram more applications into one
processor. Companies such as VMWare offer these services, which
Dave Thornley, service and support manager at Sheffield Hallam
University, recently used to help freeze the rapidly rising power
drain in his datacentre. "The power draw on the datacentre was
increasing, as was the cost of paying for it," he says, adding that
power consumption presented both a financial and a capacity
problem. "We run a large uninterruptible power supply in the
machine room and that was approaching capacity, to the point where
we would not be able to add any more equipment."
The university ran a huge variety of servers, ranging from 1U
rack units through to large clustered database systems. It was
adding 20 to 30 servers a year on average, says Thornley, but each
server's processor ran at only about 15% utilisation.
It used VMWare's ESX software running on two four-way
Xeon-powered Hewlett-Packard DL580 servers to create roughly 35
virtual machines running different applications. It has been out of
the pilot phase for six months. "We have yet to move on the
consolidation, in terms of pulling machines out and throwing them
away, but every new server is going onto VMWare," says
Thornley.
Power for the two 2 DL 580 servers costs about £1,600 a year; 25
DL 360 servers, which a virtualised DL 580 replaces, would cost
£12,025 a year, representing a saving of £10,425, according to
Thornley's figures - which do not include the costs of cooling.
However, the software cost must be factored into the figure.
But while people like Thornley concentrate on the datacentre,
Sumir Karayi, CEO of 1E, is more worried about desktop machines.
Whereas finance is sometimes a secondary consideration to capacity
in the datacentre, money is everything on the desktop. Karayi's
company sells Nightwatchman software, which is designed to manage
power consumption on desktop computers.
Sleep mode and power management facilities in corporate PCs are
often disabled, says Karayi. "IT departments can always tell
facilities that they don't care how much power costs because they
have to update PCs with virus patches because it is a security risk
to the business," he says. "So a lot of companies we go to today do
not turn off computers at night and weekends."
Nightwatchman allows IT departments to turn PCs on and off
remotely to save costs. A December 2004 report from research firm
Intertek about household computing suggests that a consumer PC will
use about 300 kilowatt hours (kWh) a year. Even if managing power
consumption on a PC saves only a few tens of pounds a year, a large
company could begin to realise significant savings.
The alternative is to go with a thin client that uses fewer
power-hungry components. Richard Barrington, head of government
affairs for computer supplier Sun Microsystems, promotes the Sun
Ray thin client. "We share one processor between 25 users and that
sits in the datacentre somewhere," he says. "The overall energy
consumption of a Sun Ray is 85%-90% below that of a PC."
Both Karayi and Barrington are disappointed at the
government-funded Carbon Trust, which advises UK businesses on how
to cut energy consumption with a view to reducing the UK's carbon
emissions. The trust recently turned down Karayi's application to
have energy-saving technology used in PCs added to the Energy
Technology List (ETL), and has also told Sun that ICT equipment is
a low priority, says Barrington.
Companies purchasing technologies and products listed on the ETL
can benefit from a 100% tax write-off on their capital expenditure
in the first year, as opposed to the conventional staggered
reimbursement, which occurs in yearly 25% increments. But the
Carbon Trust, which reviews the ETL each year and makes
recommendations to the UK government, has steadfastly refused to
include ICT equipment on the list. Why?
It is a question of volatility and practicality, says Garry
Feldgate, director of delivery and external relations for the
Carbon Trust. Once a technology category has been added to the ETL,
manufacturers can apply to have individual product models added to
the accompanying product list. These products generally stay on the
list for years at a time, but the volatile nature of the IT
business means products become obsolete very quickly, making list
management a problem, says Feldgate. "I have an IBM laptop, which I
was issued with four months ago. It was the latest IBM laptop, and
it is now discontinued," he laments. He adds that the savings from
energy-efficient computer equipment dwarf what a company would
receive from a tax break on that kit.
But there must be some answer, and the UK government doesn't
seem particularly bothered about finding one. It has not joined the
voluntary European initiative, called the Group for Energy
Efficient Appliances (GEEA), which promotes the use of
energy-efficient office equipment. DEFRA refuses to comment.
Clearly, if companies want to conserve power on the desktop,
then the same rules apply to the datacentre - do it yourself. You
will have to find your own case to put to the finance director.
Those IT managers who care about the environment will have to sneak
it in, hidden beneath a balance sheet.
Case study: Drug company gets injection of extra
power
If there is one sector that requires more than its fair share of
number-crunching, it is life sciences. Inpharmatica, a company that
carries out drug discovery computing on a contract basis for large
pharmaceutical firms, found its existing hosted computing
infrastructure bursting at the seams.
It had about 2,500 CPUs running in Sun and IBM 1U rack servers
located in its own offices and a hosted datacentre. It needed to
move to a higher-density computing infrastructure to cope with the
work it does calculating the relationships between proteins.
Steve Tringham, IT manager at Inpharmatica, moved to IBM blade
servers running 400 3.5GHz Intel Xeon processors with 64-bit
extensions. These used more electricity than AMD's rival Opteron
chips, but Tringham wanted as much processing power as he could
find.
The new solution beefed up Inpharmatica's number-crunching
capability, but it came at a cost. An average rack uses 3Kwatt of
electricity, says Tringham, whereas the specialised racks used for
the IBM blade servers need 18Kwatt each. Inpharmatica's existing
hosting company could not provide that much power, and it would
also stretch his own server room. Energy capacity was a potential
showstopper.
"People like IBM and other suppliers pitch high-density
computing, which is great because you use less space," he says.
"But if the computer rooms in your building can only cope with
18Kwatt in total, it is still an empty computing room. Until you
can spend the money to put a load more power and air conditioning
into the same space, you have not got a winner."
The company moved its whole infrastructure to Globix, a company
that provides hosting facilities in the City of London. According
to director Christian Eckley, Globix built out very high-capacity
datacentres just before the dotcom bubble burst, leaving it all
dressed up with nowhere to go, and with a nasty period spent in
Chapter 11 bankruptcy. Nevertheless, Globix bounced back, and now
uses its enhanced power capacity to provide high-density hosting
for customers such as Inpharmatica.
Now, Tringham's server infrastructure is consolidated and, while
the energy part of its hosting cost is likely to be rather large,
at least he does not have to worry about finding enough power to
make the computers - and of course the air conditioning - work.