We know that organisations are becoming more focused on the
power usage across the various aspects of their business. For those
companies with significant datacentre operations the consumption of
power by IT is getting especially close attention. In fact, the
recent rises in energy costs and the expectation that costs will
remain erratic, but continue to move upwards means that a CIO not
looking at
power usage within the datacentre is heading for problems.
The first challenge - as research shows - is that few CIOs have
any idea of the power that a given datacentre uses in total - never
mind to any level of granularity. If a datacentre is housed in the
same building as other business functions and does not have its own
power meter it is very difficult to identify what is used by the
datacentre and what is not. The second challenge is figuring out
what power is being consumed by individual pieces of IT equipment,
and what is being consumed by the ancillary equipment that is
necessary to maintain the datacentre environment. The major
ancillary equipment power hogs are air-con and UPS - often taking
two or three times as much power as the servers, storage and
networking equipment.
The advent of two different datacentre efficiency measurements -
Power Usage Effectiveness (PUE) and Datacentre Infrastructure
Efficiency (DCIE) - means that any organisation wanting to see
where it stands against others has a means to apportion power usage
between IT equipment and ancillary equipment. Datacentre managers
need only to know the total amount of power used by the datacentre,
how much goes to IT equipment, and how much to support equipment.
Job done!
Unfortunately, this brings in several problems, not least of
which is that two datacentre "managers" are now generally involved
- the datacentre IT manager, and the datacentre facilities manager.
Also, we need to look at the granularity of the power figures that
are to be provided. Do you want something high level, at the level
of power to a rack? In this case, send in the facilities engineers
with power clamps and they will provide you with direct readings
that will give a snapshot of what was happening when they clamped a
given rack or a chassis. Unfortunately, such a measurement is only
a point in time snapshot and will not capture how power usage
changes as workload levels change. More effective is a measurement
that is more continuous and is based on usage per IT asset. For
this you will need specialist skills.
One company that provides such skills is UK-based
End2End. Set up
by a couple of ex-Hewlett-Packard and IBM veterans, the design and
build of datacentres is taken very seriously, and brings together
the viewpoints from the facilities and IT sides of the fence to
provide the best solution to the customer. For example, when it
comes to looking at power within the datacentre, End2End's view is
that if you cannot measure it, you cannot do anything about it.
Furthermore, if you can measure it, you need to be able to
understand it, otherwise it is just more meaningless data.
The majority of those who provide power measurement systems
provide direct readout of power utilisation at the power
distribution strip. Some of these are evolving to provide highly
granular levels of detail - either via optical readouts, or via
facilities-based remote information aggregation and display.
End2End, however, took a very IT view of what the datacentre
manager's real needs are - and built on technology that has been
around for a long time.
Power usage is still measured at a granular level at the
distribution strip, but is then converted into a standard
management information base (MIB) data stream through the use of a
standard network management protocol (SNMP) trap. Therefore, the
data can be sent through to any SNMP-compliant systems management
product - such as IBM Tivoli, CA Unicenter, BMC Patrol, or HP
Openview. The scripting languages within these systems can then be
utilised to present anything untoward in a manner which makes a
datacentre manager more able to deal with it directly - or at the
very worst, be able to point a facilities person more directly to
where the problem lies - and to understand what the possible
ramifications are should the engineer decide to try to swap out the
offending electrical component on a live system.
So, by taking a more hybrid approach to the problem, not only
does End2End provide you with the data you need to calculate your
PUE/DCiE numbers, but also provides you with a means of identifying
root cause when it comes to power issues, and in assessing the risk
of dealing with the problem.
Having such information to hand can help as architectures
change. For example, the move to blade architecture means that
power densities become higher. Layering virtualisation on the top
of this causes heat problems to become dynamic - a chassis running
four virtual images may (or may not) need more cooling than one
that is running eight such images, depending on the workloads these
images are dealing with and how they have been provisioned. By
measuring the power usage of the underlying chassis and individual
blades and other components, intelligent decisions can be made as
to where a new virtual server should be spun up so as to minimise
heat issues, allowing cooling costs to be minimised.
To solve the problem completely in the datacentre requires more
than just a good knowledge of how best to use power within the
facility and across the IT assets, and End2End brings together
tools and systems from a range of different suppliers which, when
combined with their own skills, should provide the optimum
datacentre design for the customer. Although a small company,
End2End has the capability to call on external auxiliary resources
to meet variations in its project load. With an impressive list of
reference customers including the Thames Valley Police, the NHS and
Purple Parking, it is a company worth talking to if you are looking
at a new, or a major change to an existing, datacentre. Just make
sure that both your IT and facilities managers know and understand
who will have the final say on how energy will be managed from
there on.