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Four Trends Driving the Future of Data Center Design

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					                                                    A White Paper from the Experts
                                                    in Business-Critical ContinuityTM




The Four Trends Driving the Future of Data Center
Infrastructure Design and Management
Introduction                                        technologies, along with more advanced
                                                    monitoring and management systems, to
Throughout the first decade of the 21st             address the reliability issues facing high-
century, countless new technologies,                density data centers.
unprecedented business demands, and
expanding IT budgets created the modern             But the pace of change and inability
data center. On the cusp of this century’s          to forecast future demand remained a
second decade, the data center finds itself         challenge. This challenge was increasingly
balancing efficiency and availability while         being met by new infrastructure solutions
computing demand and energy costs are               that could more efficiently adapt to short-
increasing and IT budgets are contracting.          and long-term change.
Looking ahead to the next 10 years, the
companies emerging as leaders will be the           At the same time, a new issue was emerging:
ones that are able to maintain or improve           energy consumption. According to a 2008
availability while implementing technologies        Digital Realty Trust survey of senior data
and services that reduce costs by improving         center decision-makers, power usage of data
design, management and operating                    centers (average kW use per rack) jumped
efficiency. This paper reviews four trends that     12 percent from 2007 to 2008. Looking back
will drive these changes.                           further, the Uptime Institute reports data
                                                    center energy use doubled between 2000
The data center as we know it today started         and 2006 and predicts it will double again by
to take shape as the dot-com bubble                 2012. With this in mind, the industry started
expanded in the late 1990s. Growth slowed           to turn its attention to reducing data center
when the bubble burst, but by 2003 the              energy consumption.
pace of change was accelerating again.
Server shipments in the fourth quarter of           Those efforts ramped up in the second
2003 were 25 percent higher than the fourth         half of 2008 as the U.S. economy entered
quarter of 2002 and continued to grow at            a deep recession and companies were
a double-digit rate the next two years as           forced to find ways to reduce spending. IT
IT organizations scrambled to meet the              organizations began to look seriously at
nearly insatiable demand for computing              energy efficiency in terms of cost savings as
and expectations for 24x7 availability.             well as environmental responsibility. This
In the absence of management tools to               is reflected in survey data compiled by the
help predict future capacity, data centers          Data Center Users’ Group (DCUG). DCUG
routinely were built to handle capacities two       members surveyed in 2005 did not include
to three times the initial requirements.            energy efficiency in their top five data center
It wasn’t only the number of servers that           concerns. In spring of 2008, efficiency made
was growing but the density and power               the list at No. 5. In spring of 2009, efficiency
consumption of those servers. Server                had moved to the second position (Figure 1).
density rose rapidly between 2000 and
2005, allowing more computing power                 The challenge for data center managers
to be packaged in smaller enclosures.               now is to maintain or improve availability in
Racks that once had held 8 or 12 servers            increasingly dense computing environments
were being packed with as many as 48                while reducing costs and increasing
servers. The industry responded with next-          efficiency. A rash of well-publicized data
generation UPS and density-specific cooling         center outages in 2008 and 2009 led to




                                                1
 Top Five Data Center Concerns
                Fall 2005                                 Spring 2008                         Spring 2009                                         Fall 2009
           Heat Density                                   Heat Density                        Heat Density                                    Availability
                                                                                                                                             Infrastructure
         Power Density                                 Power Density                              Efficiency
                                                                                                                                             Management
              Availability                                 Availability                Adequate Monitoring                                   Heat Density
   Fuzzy growth plans                               Adequate Monitoring                          Availability                                     Efficiency
 Technology Changes                                             Efficiency                  Power Density                                   Power Density
 Adequate Monitoring

Figure 1. Summary results from Data Center Users Group surveys. Source: DCUG

speculation that cost-cutting was resulting                                            accomplished by establishing data center
in increased downtime. In the wake of                                                  infrastructures that leverage four distinct
those outages, respondents to the fall 2009                                            opportunities to enhance efficiency without
DCUG survey showed a renewed respect for                                               compromising availability. These are the
availability. It jumped from the fourth most                                           opportunities that will drive data center
important concern just six months earlier to                                           infrastructure design and management in
the number one concern (Figure 2).                                                     the coming years.
                Fall 2008                                                                               Fall 2009
                                    0%        10%   20%     30%      40%     50%                                            0%        10%   20%     30%        40%   50%


                                     1%                                                                                      1%
     1 – Reducing energy usage                                                               1 – Reducing energy usage
            is our main priority                                                                    is our main priority

                                         2%                                                                                      2%
                               2                                                                                       2



                                               7%                                                                                     6%
                               3                                                                                       3



                                                          21%                                                                                17%
                               4                                                                                       4



                                                           23%                                                                               15%
                               5                                                                                       5



                               6                           23%                                                         6                           25%



                                                           23%                                                                                           31%
7 – Maintaining high availability                                                       7 – Maintaining high availability
             is our main priority                                                                    is our main priority




The likely reason again is economic: one                                               Defining Efficiency
significant outage can be so costly that it
wipes out years of savings achieved through
                                                                                       Efficiency is the ability to produce an output
incremental efficiency improvements (Figure 3).
                                                                                       with a minimum of effort, expense or waste.
To meet the sometimes conflicting                                                      In the data center, efficiency traditionally has
objectives of reducing costs and increasing                                            been used to refer to energy. But in reality,
availability, data center management must                                              energy is just one of the resources consumed
enter a new stage of maturity. That can be                                             by a data center. And energy efficiency, while




                                                                                   2
7                                                                                     without increasing operating or
6                                                                                     management costs has been just as
                                                                                      successful at improving efficiency as
5                                                                                     one that cuts costs by half.
4                                                                                     Taking advantage of the
                                                                                      opportunities outlined in this paper
3
                                                                                      enables IT organizations to more
2                                                                                     efficiently deploy and use all of their
1                                                                                     resources throughout the life of the
                                                                                      data center—including physical space,
0
                                                                                      capital equipment dollars, design and
     Banking     Energy           Telecom Manufacturing Retail Healthcare
                                                                                      management time, service costs and,
                                             Downtime Cost                            yes, energy.
                                               ($M/Hour)
                                                                                      1. Density Creates Efficiency
                                                                                       Data centers already are moving
                                                                                       toward high-density computing
                                                                                       environments as newer, more
    important, is just one chapter in the larger
                                                                               dense servers are deployed. In the fall 2009
    data center lifecycle story. For example,
                                                                               DCUG survey, respondents indicated they
    is a system that offers excellent operating
                                                                               expect average rack densities to be 11 kW
    efficiency but can’t accommodate growth
                                                                               in two years and 17 kW within 10 years—
    or change really that efficient? How about
                                                                               significantly higher than the 7.4 kW average
    a system that offers small energy efficiency
                                                                               when the survey was taken (Figure 5). The
    gains but exposes critical IT systems to
                                                                               reasons cited for moving to higher densities
    greater risk?
                                                                               include saving facility space and reducing
                                                                               energy costs. This indicates there is growing
    That’s why a data center efficiency equation
                                                                               understanding of the savings that can be
    should involve Design, Management and
                                                                               achieved through efficiency; however,
    Operation (Figure 4). Of course, data center
                                                                               the magnitude of the savings available
    output is the other side of this formula. A
                                                                               through increasing density continues to be
    data center that can double its capacity
                                                                               underestimated.

                                  Design &                                     For example, industry estimates put the cost
                                 Deployment                                    of building a data center (the building shell
                              ■ Shorten Time                                   and raised floor) at $200-$400 per square
                              ■ Minimize Space
                                                                               foot. By building a data center with 2,500
                                                                               square feet of raised floor space operating
                                                                               at 20kW per rack versus a data center with
        Management                                                             10,000 square feet of raised floor space at
                                                       Operation
         & Planning                                                            5 kW per rack, the capital savings could
      ■ Improve Performance                      ■ Increase Availability       reach $1 - $3 million. Operational savings
      ■ Increased Control                        ■ Reduce Energy
                                                                               also are impressive – about 35 percent of the
                                                                               cost of cooling the data center is eliminated
                                                                               by the high-density cooling infrastructure.
    Figure 4. Energy is just one of the factors that
    contribute to data center lifecycle costs.

                                                                           3
The days when data centers opened with                18
huge areas of unused floor space set aside            16
for a decade’s worth of growth are coming             14
to an end. Instead of building out, like a city       12
with a growing population supported by                10
sprawling suburbs, data center designers and          8
managers are beginning to understand it is            6
more efficient to build “up” and replace the
                                                      4
sprawl with higher density racks. Sixty-three
                                                      2
percent of the respondents to the fall 2009
                                                      -
DCUG survey indicated they plan to make
                                                           2006    2007   2008    2009   In 2 years   In 10 years
their next data center new build or expansion
a high-density (>10kW/rack) facility.
This does require a different approach to
infrastructure design, including:
                                                      movement—containment. Aisle containment
                                                      prevents the mixing of hot and cold air
High-density cooling: High-density cooling
                                                      to improve cooling efficiency. While hot-
brings cooling closer to the source of heat
                                                      aisle and cold-aisle containment systems
through high-efficiency cooling units
                                                      are available, cold aisle containment
located near the rack to complement the
                                                      presents some clear advantages. Cold aisle
base room air conditioning. These systems
                                                      containment can be used with or without
can reduce cooling power consumption
                                                      conventional raised-floor cooling, can be
by as much as 32 percent compared to
                                                      retrofitted easily into existing raised-floor
traditional room-only designs. Pumped
                                                      data centers and works in tandem with the
refrigerant solutions remove heat from the
                                                      raised floor as well as with high-density
data center more efficiently than air-cooled
                                                      cooling systems to produce highly efficient
systems and provide incremental energy
                                                      cooling. By integrating the cold aisle
savings of between 25 and 48 percent
                                                      containment with the cooling system and
based on kW of cooling capacity per kW of
                                                      leveraging intelligent controls to closely
heat load. Originally designed to address
                                                      monitor the contained environment,
hot spots or zones within the data center,
                                                      systems can automatically adjust the
high-density cooling systems have become
                                                      temperature and airflow to match server
a basic building block of the data center of
                                                      requirements. This results in optimal
the future, delivering the ability to meet the
                                                      performance and energy efficiency.
needs of today’s 10, 20 and 30 kW racks
while offering the ability to support densities
                                                      High-density power distribution: Power
of 60 kW or higher in the future. Also, these
                                                      distribution has evolved from single-stage to
cooling systems can use high-efficiency
                                                      two-stage designs to enable increased density,
pumped R134a refrigerant that turns into
                                                      reduced cabling and more effective use of
a gas if it ever touches the air. This prevents
                                                      data center space. Single-stage distribution
an unlikely leak from ever damaging IT
                                                      often is unable to support the number of
equipment and triggering an outage.
                                                      devices in today’s data center as breaker space
                                                      is expended long before system capacity is
Intelligent aisle containment: The
                                                      reached. Two-stage distribution eliminates
efficient and well established practice of
                                                      this limitation by separating deliverable
hot/cold aisle alignments sets up another
                                                      capacity and physical distribution capability




                                                  4
into subsystems. The first stage receives              unavailable for about an hour and suffered
high-voltage power from the UPS and can be             further interruptions over an additional 3.5
configured with a mix of circuit and branch-           hours. Pingdom, a company specializing in
level distribution breakers. The second                uptime monitoring, estimated the cost of the
stage or load-level units can be tailored to           outage to the firm at between $7 million and
the requirements of specific racks or rows.            $32 million.
Growing density can be supported by adding
breakers to the primary distribution unit and          Renewed concern over the possibility of
adding additional load-level distribution units.       outages was reflected in the latest DCUG
Additionally, higher amperage in-rack power            survey. Availability vaulted back to the top
distribution units (PDUs), like the Liebert            of the key issues list – now a concern for 56
MPX, can be deployed to manage higher                  percent of respondents versus just 41 percent
electrical requirements within the rack. These         six months earlier (Figure 1).
systems can provide 60amp capacity per strip,
compared with 15 amp for traditional rack              A large percentage of outages are triggered
power strips, and also feature a modular design        either by electrical or thermal issues that can
that makes it easy to add additional receptacles       be minimized or eliminated with adequate
or support high-density equipment.                     power and cooling solutions. The challenge
                                                       is optimizing the efficiency gains available
Together, these new advances in power and              in power and cooling approaches with IT
cooling technology are enabling high-density           criticality and the need for availability. Some
environments to achieve the same levels                of the choices to be made and the potential
of availability and scalability as low density         trade-offs between efficiency and availability
environments while offering significant savings        include:
in design and operating costs.
                                                       Uninterruptible Power Supply: Data
2. Availability Makes a Comeback                       center managers should consider the power
                                                       topology and the availability requirements
The second area of opportunity in the coming           when selecting a UPS. In terms of topology,
decade involves optimizing IT performance              online double conversion systems provide
while achieving high levels of availability. In the    better protection than other types of UPS
race to achieve improved energy efficiency—            because they completely isolate sensitive
and, ultimately, cut costs—some businesses             electronics from the incoming power source,
lost sight of that balance and paid the price          remove a wider range of disturbances and
with costly outages. The Uptime Institute              provide a seamless transition to backup
issues Flash Reports to its members when it            power sources. Online double conversion
sees a data center experiencing failures that          systems are the preferred choice for the
could occur at other sites with the same kind          data center, and are displacing standby or
of infrastructure equipment. According to              line-interactive UPS systems in network
an August 2009 article in Computerworld, it            access rooms as overall network availability
sent out six Flash Reports in all of 2008 — and        requirements rise. UPS design also should
17 in just the first eight months of 2009. In          be considered. There is growing interest,
addition, many of these outages were reported          based on efficiency and other factors such
in the media, including a popular online               as floor space, in utilizing transformerless
financial transaction provider, which suffered         UPS modules in high-power, three-phase
an outage in August of 2009. The service was           applications. However, for large enterprise




                                                   5
data centers and other applications                 the cooling system, can be an effective
where availability is critical, a traditional       approach to lowering energy consumption
transformer-based UPS still provides the            if they are properly applied. Two base
highest reliability. Transformers within the        methods exist, air side and water side.
UPS provide fault and galvanic isolation,           Water-side economizers provide the benefit
which prevents fault currents from entering         of bypassing the compressor, using fluid from
critical systems and causing outages.               the cooling tower or drycooler system to
Technology developments and configuration           reject heat directly when conditions permit.
options allow the latest generation of              The components in expensive IT systems
transformer-based designs to operate at             are sensitive and can be damaged by
higher efficiencies compared to previous            gaseous contamination and particulates
designs, making them more comparable                presented in air side economizers if not
to the transformerless models in the                properly filtered. Corrosion is another
marketplace. In fact, a transformerless             issue to be considered. Filters, automated
UPS only achieves better efficiency than            dampers, bypass circuits, air-quality
a traditional transformer-based UPS at              monitoring, humidity management and
loaded capacities greater than 40 percent,          control systems can help, but all add
with real cost savings coming at capacities         significant construction costs along with
greater than 60 percent. Most dual bus UPS          operation and maintenance expense.
configurations operate under 50 percent
load for 99.99 percent of the time and so           Water-side economization allows
would produce no efficiency savings with a          organizations to achieve the benefits
transformerless UPS.                                of economization without the risks of
                                                    contaminants presented by air-side
Advancements also have been made in                 approaches. All approaches have pros and
how UPS systems are employed to reduce              cons. Data center professionals should
power losses. Energy conversion or “eco”            discuss the appropriate applications with
modes allow these systems to achieve                local experts.
efficiencies comparable to less robust
technologies, but not without affecting             Service: A proactive view of service
availability. In eco mode the UPS switches          and preventive maintenance in the data
to static bypass during normal operation.           center can deliver additional efficiencies.
When power problems are detected, the               Making business decisions with the goal
UPS automatically switches back to double           of minimizing service-related issues may
conversion mode. This allows double-                result in additional expense up front, but
conversion UPS systems to achieve 97                it can increase life cycle costs. Meanwhile,
percent full load operating efficiency, but         establishing and following a comprehensive
could allow certain faults and conditions           service and preventive maintenance program
to be exposed to the load. Some systems             can extend the life cycle of IT equipment
claim 99 percent efficiency in eco mode, but        and delay major capital investments. An
that comes with a further compromise to             Emerson Network Power study of the impact
availability. Proper application of eco mode        of preventive maintenance on UPS reliability
technology should be enforced.                      revealed that the Mean Time Between
                                                    Failures (MTBF) for units that received two
Economization: Economizers, which use               preventive maintenance service visits a
outside air to reduce work required by              year is 23 times better than a UPS with no




                                                6
preventive maintenance visits. According               Newer data center cooling technologies can
to the study, reliability continued to                 adapt to change and deliver high-efficiency
steadily increase with additional visits when          at reduced loads. Specifically, digital scroll
conducted by highly trained engineers.                 compressors allow the capacity of room air
                                                       conditioners to be dynamically matched to
The move to introduce more efficient power             room conditions, minimizing compressor
and cooling technologies into the data                 cycling, which reduces wear and creates
center will continue for the foreseeable               energy savings of up to 30 percent over
future, but when these technologies                    traditional technologies. Variable speed
introduce greater risk than the technologies           drive fans allow fan speed and power draw
they displace, the economics of downtime               to be increased or reduced to match the load
will drive organizations to rethink their              resulting in fan energy savings of 50 percent
priorities of optimizing efficiency and                or more.
availability.
                                                       New designs in power systems allow
3. Change Remains a Constant                           improved component performance at
                                                       40-60 percent load compared to full load.
Flexibility is critical in today’s data center         Power curves that once showed efficiency
environment and will be imperative for                 increasing with load now have been
businesses in the years ahead. IT demand               effectively flattened as peak efficiencies can
fluctuates depending on the time of                    be achieved at important 40-50 percent load
day (peaking during business hours, for                thresholds.
example), the day of the week (banks may
see significant increases in demand on Friday          In the distribution system, new transformers
paydays), or certain business cycles (such             are more efficient at half load than they
as holiday shopping season for retailers).             are at full load. Modular in-rack PDUs allow
The data center also has to adjust to more             rack power distribution systems to adapt to
long-term variations such as organizational            changing technology requirements through
growth and the addition of new applications            the addition of snap-in modules. They also
requiring IT support. Simply put, the data             provide monitoring at the receptacle level to
center is a dynamic environment and                    give data center and IT managers the ability
optimizing performance in that environment             to proactively manage changes.
requires a flexible infrastructure.
                                                       Adding digital control capabilities to the
Previous generations of infrastructure                 power and cooling systems is another way
systems were unable to adjust to variations in         to better match performance to demand
load. Cooling systems had to operate at full           and increase efficiency. As an example, the
capacity all the time, regardless of actual load       Liebert iCOM control system coordinates
demands. UPS systems, meanwhile, operated              operation among multiple precision cooling
most efficiently at full load, but full load           units, allowing them to function as a single
operation is the exception rather than norm.           coordinated team while also providing
The lack of flexibility in the power and cooling       advanced diagnostics for the entire
systems led to inherent energy inefficiency.           operation, leading to improved efficiency
                                                       and availability.
This creates an especially large opportunity
for cooling systems as cooling can account             On the power side, scalable UPS solutions
for 35 percent of data center energy costs.            allow data center managers to add capacity



                                                   7
when needed. SoftscaleTM technology, for             benefits is a comprehensive infrastructure
example, enables businesses to purchase              management solution.
the UPS capacity they need today while
providing the flexibility to ensure additional       Infrastructure management typically
capacity in the future through a software            progresses through phases. The first phase
modification. Thanks to the flattened UPS            should involve a data center assessment
efficiency curve mentioned previously,               to provide insight into current conditions
Softscale systems deliver the same high              in the data center and opportunities for
efficiency at 50 percent utilization as at           improvement. After establishing that
100 percent. This development has had                baseline, a sensor network is strategically
the added benefit of allowing smaller data           deployed to collect power, temperature
centers to take advantage of the higher              and equipment status for critical devices
reliability and lower cost per kilowatt of           in the rack, row and room. Data from the
a centralized UPS compared to operating              sensor network is continuously collected
several smaller UPS systems.                         by centralized monitoring systems—such as
                                                     Liebert SiteScan or Liebert Nform—to not
Where previous generation data centers               only provide a window into equipment and
were unable to achieve optimum efficiency            facility performance, but point out trends
at anything less than full load, today’s             and prevent problems wherever they may
facilities can take full advantage of these          be located. For example, if an unmonitored
innovative technologies to match the data            branch power circuit operating at 80 percent
center’s power and cooling needs more                or more of full capacity has a load blindly
precisely, regardless of the load demands            applied, it could cause the distribution
and operating conditions.                            breaker to trip, powering down that entire
                                                     distribution leg. Or take the addition of blade
4. Visibility and Control                            servers to an unmonitored rack. Users could
Enables Optimization                                 be at the thermal threshold of heat creep,
                                                     unknowingly subjecting systems to serious
Today’s data center supports more critical,          problems.
interdependent devices and IT systems
in higher density environments than                  Another example involves batteries,
ever before. This fact has increased the             often described as the weakest link in the
complexity of data center operations – and           power chain. The best way to determine a
created the need for more sophisticated and          battery’s health without discharging it is
automated approaches to IT infrastructure            to use a monitoring system that measures
management.                                          the internal resistance of all of the cells in
                                                     the battery, utilizing an integrated battery
Gaining control of the infrastructure                monitoring service that combines state-
environment leads to an optimized data               of-the-art technology with proactive
center that improves availability and                maintenance and service response.
energy efficiency, extends equipment life,
proactively manages the inventory and                Centralized or remote infrastructure
capacity of the IT operation, increases              monitoring provides this real-time control,
the effectiveness of staff and decreases             historical performance trending, alarm
the consumption of resources. The key to             notifications and event escalations to
achieving these performance optimization             minimize or eliminate downtime. In addition,




                                                 8
                   Data Center Issues
                                                        0%   10%   20%         30%     40%   50%     60%   70%   80%   90%   100%


                               Experienced hot spots                                               55%

                                    Run out of power                             28%

Experienced a “Water Event” (leak or water incursion)                            28%

                              Experienced an outage                              27%

                        NA – Have not had any issues                     23%

                                   Run out of cooling                20%

                               Run out of floor space                16%

                                               Other         6%




  Figure 6. Making strides in the infrastructure management area of opportunity will help reduce
  the number of issues faced by data center managers during the course of a year.

users can manage energy consumption                                            the three cycles: design and deployment,
through thermal and power metering.                                            operations, and management and planning.

The final phase is optimization. A                                             Data centers moving to a higher density IT
comprehensive infrastructure management                                        space can improve efficiency as a result. Yet,
system can help data center managers                                           data center, IT and facilities managers must
improve equipment utilization, reduce server                                   take steps to avoid compromising availability
deployment times and more accurately                                           as the higher density puts additional stress
forecast future equipment requirements,                                        on the power and cooling infrastructure.
resulting in operating and capital expense                                     To more efficiently support the more
reductions. Managers not only improve                                          complex IT environment, the data center
inventory and capacity management,                                             infrastructure must be able to continually
but also process management—ensuring                                           adjust to changes in capacity and demand.
all assets are performing at optimum                                           The best way to make those adjustments
levels. Effective optimization can provide                                     and truly optimize performance is through
a common window into the data center,                                          advanced visibility and control that
improving forecasts, managing supply and                                       comes with comprehensive infrastructure
demand, improving levels of efficiency and                                     management.
availability. For example, a large retailer
used Aperture infrastructure management                                        It all starts at the design and deployment
software to reduce server deployment time                                      stage, when companies can leverage pre-
by 30 percent while slashing the error rate                                    engineered solutions and high-density
from 25 percent to 0, using proven process                                     architectures to reduce the time, space
management functionality.                                                      and capital required for construction
                                                                               of the building. During operation, data
Conclusion                                                                     center managers can reduce costs by using
                                                                               efficient technologies and strategies while
During the data center’s next decade,                                          simultaneously decreasing downtime
opportunities to improve efficiency and                                        costs by employing high-availability
optimize performance will exist throughout                                     configurations. And additional savings




                                                                     9
are available by using infrastructure
management controls to streamline
operations and facilitate a comprehensive
maintenance program.

The key is to look beyond energy when
considering efficiency and to take every
opportunity throughout the lifecycle of the
data center to achieve efficiencies—without
compromising performance.




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                                                                                          completeness in this literature, Liebert Corporation assumes no
                                                                                          responsibility, and disclaims all liability for damages resulting
                                                                                          from use of this information or for any errors or omissions.

                                                                                          © 2010 Liebert Corporation. All rights reserved throughout
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