The Semantics of ‘Efficiency’

Glance at a magazine or the Web and it will not take long to discover product claims that sound wonderful, but that mean rather less: ‘excellent returns,’ ‘exclusive offer,’ and ‘better miles per gallon’ are all common examples. The descriptors “efficient” and ‘efficiency” sound so much more definitive and striking, but, in fact, can fall into the same category. The problem is twofold:

1.       ‘Efficient’ is a very generic term-glibly applied, easily accepted, and apparently meaningful, it is in fact usually full of potential for debate.

2.       ‘Efficiency’ is a relative state-much as everyone is ‘tall’ compared to at least one other person and ‘cold’ weather means something different if you live in Mexico or Moscow, ‘efficient’ is a function of comparison.

A clear definition can help. The Concise Oxford Dictionary lives up to its name, saying efficient is “productive with minimum waste or effort.” For the purposes of this paper, IT efficiency is deemed to be the use of the minimum amount of relevant resources at any time to get a certain amount of work done. This makes ‘efficiency’ not only measurable and subject to continuous improvement, but also broad-after all, being efficient (even at a relatively good level) in one area of IT (power consumption for instance) doesn’t mean the overall approach is at all efficient. To give a specific example, you could have power-efficient drives (say, 1 TB SATA), but if you only use a tiny amount of their capacity in order to sustain a certain IO rate, then it’s hard to argue that this is the ‘most efficient’ approach. There’s an old joke that if you put one foot in a bowl of scalding water and one in a bowl of ice, on average, you’re comfortable! IT and storage are the same-two wrongs do not make a right.

Although changing ingrained industry semantics is tough, Compellent can help by putting storage ‘efficiency’ under a magnifying glass to show us what it really means. In helping itself, Compellent might point to the virtues of a handful of other vendors, but will no doubt point to the shortcomings of many more. The current global economic downturn has made ‘efficient’ a marketing cry almost as loud as the ‘green’ mantra of the last few years-and it is just as susceptible to hype. But, in a world of storage-efficiency claims, what actually matters and how can users judge between competing vendors?

The Importance of Storage Efficiency: Operations and Economics

Why is ‘efficiency’ in storage such a big deal? As mentioned, it is partly because of economic conditions; however, it is also a result of the continuing challenge to simultaneously manage data growth and contain costs. A recent ESG research survey[1] found two important details -

• The greatest challenge users have with respect to their storage environment is ‘keeping pace with overall data growth’
• The number one business initiative users believe to be significantly impacting their storage spending over the next two years is ‘internal pressure to reduce the overall costs of doing business’

The generic answer to balancing this equation is clearly to add ‘efficiency’ into the mix. Some of the main specific areas that can be addressed are:

Environmental resource needs – reductions in the power and cooling requirements and improvements in space efficiency (PCSE for short) of storage. This can reduce costs that could free up budget to help cope with data growth.

Capacity and utilization – ensuring that purchased storage is a suitable type and is well-used, both in terms of the capacity being filled and of data being on the optimum storage at varying stages of its life (whether dynamic or persistent, active or inactive).

Operational ease - automating operations to reduce and simplify personnel needs; thus reducing training, multiple platform learning, and providing management reports.

Vendors can be ‘efficient’ in one area-to a greater or lesser extent-but virtue in one aspect can be undone by a failing in another. The desire for overall optimum efficiency is not driven by altruism, but rather by cold hard financial needs. Very recent ESG research (see Figure 1) on spending intentions shows that reducing operational expenditures is the most important consideration in justifying IT investments over the next 1-2 years.

As the chart shows, while reducing capital expenditure remains a crucial consideration, what users want most is to invest (which the same survey found they will continue to do) where will be ‘spending money to save money.’ In colloquial terms, this means users want to-and will-buy into ‘enhanced efficiency.’ Indeed, the ESG survey found that storage virtualization is a top storage initiative over the next 12-24 months. Furthermore, the prevalence for spending on storage virtualization is much higher (by roughly 50% ) amongst organizations that had cited cost reduction as a major factor in their storage spending as compared to those that had not. Users will pay for efficiency! While there is no suggestion that any reduction in effectiveness can be accepted to achieve this (getting the job done has always been ‘job number one’ in IT), it is interesting to note that the cat is out of the bag when it comes to increased storage efficiency. Innovative vendors-such as Compellent-have shown that this is not a zero sum game. It is perfectly conceivable to have your cake (of effectiveness) and eat it (be more efficient) too. As a result, it is unlikely that the storage industry will ever ‘un-invent’ this particular wheel!

Compellent’s Efficiency Capabilities

Against this background, Compellent has a wide range of offerings with capabilities that address the main areas of opportunity. While naturally taking advantage of generic improvements that are available to all vendors (such as improved disk drives and power supplies), the company seeks to develop enhanced efficiencies. These are largely delivered by the high level of virtualization in Compellent storage systems. That said, they are enhanced by an overall attitude in Compellent’s ‘DNA;’ it continues to ‘push the envelope’ to develop innovative, differentiated tools that drive ever-increasing storage efficiency. It is worth recalling the initial definition (efficiency is the use of the minimum amount of relevant resources at any time to get a certain amount of work done), as we review the main features and functions Compellent offers:

Environmental Resource Control

• Automated Tiering (Compellent’s name is ‘Data Progression’) enables different data and data-activity-needs to be placed on varying, optimum storage types (soon to include solid state), optimizing PCSE requirements. It’s like ILM (Information Lifecycle Management) in a volume.
• ‘Fast Track’ ‘auto-tunes’ the most active data to the outer tracks of disks to optimize performance and in turn improves disk utilization, which reduces the spindles needed.
• ‘Thin Replication’ reduces the bandwidth needed for replication by utilizing snapshot technology and only replicating block-level changes.

Capacity/Utilization Optimization

• Thin Provisioning (the Compellent name is ‘Dynamic Capacity’) means that only written data is actually stored-and only then does it consume disk space.
• Tagged Metadata permits very granular, automated data management, enabling the ‘perpetual optimization’ of data placement.
• ‘Data Instant Replay’ (Compellent snapshot technology) uses pointers to make snaps very granular, with only block level writes consuming space.
• Windows Free Space Recovery allows free space created after a Windows file is deleted to be utilized again.

Operational Ease

• One-off software licensing is a straightforward approach that limits upfront costs and ongoing management control.
• A simple GUI minimizes training and makes administration easy. An example of the operational ease is a one button, automated restore function.
• Automation/virtualization is policy-based; it reduces management and administration efforts, as well as precluding the need for performance tuning.
• ‘Thin Import’ is an intriguing ability to virtualize data as it’s moved off of other vendors’ systems and apply thin provisioning to it.

There are two other overall positive aspects to note-part of a virtuous circle, if you will. The better you use the equipment you have, the less of it that you need; it’s often overlooked but, obviously, there will therefore be less supporting infrastructure needed (such as generators, PDUs, and so on) and you will save physical space. And, across the board-and even beyond thin provisioning-Compellent never pre-allocates space, meaning that storage is only consumed when it is actually used. Both these attributes impact OPEX and CAPEX favorably.

The summary of all the above is that, without sacrificing or compromising effectiveness, Compellent’s focus has been to relentlessly drive improved disk system efficiencies. ‘Use less and use it better’ is not the company’s tag line, but it could well be! And what is the realistic potential for such savings? How much less storage, power, space, and so on?

Users: Potential Impact and Questions for Vendors

Potential Impact

An earlier ESG Brief[2] that focused on Compellent’s ‘green’ credentials provided considerable detail on the extent of the potential OPEX and CAPEX impacts. The quick summary is that the implications and benefits for an end-user can be substantial:

• Power consumption can be reduced (mainly by tiering, data progression, and thin provisioning) by anything from a few percent to over 90%, depending on data types and application needs;
• Thin provisioning can reduce the physical disks needed by 10% to well over 50%;
• Data tiering can drive power consumption down 80% or more, as well as probably saving CAPEX (since more capacity is likely to move to larger, less $/GB devices);
• Users will not need as much physical space.

As that report stated, “… of course, the ‘laundry list’ of options is combinable, not mutually exclusive-meaning that the overall savings compared to a fully traditional environment can be genuinely breathtaking. So, to add some realism, even if a user doesn’t do everything that’s possible with the Compellent ‘suite’ and even if a user feels it’s never possible to attain the ‘maximum’ (put simply, if you apply some percentage for presumed ‘mileage variance’), there is still a very realistic potential to make dramatic and noticeable reductions in power, cooling and space requirements just by utilizing storage more efficiently.”

And, in an effort to help keep track of these bottom-line savings, Compellent offers a selection of reports that-not surprisingly, given their powerful implications in a world focused on reducing OPEX-are nicknamed ‘Hero Reports.’ Figure 2 shows an example, which allows IT managers to succinctly explain the added value they are delivering to an-often skeptical-organization.

Questions for Vendors

Users considering basing their vendor choice-to any  extent-upon efficiency as well as effectiveness should start by finding out whether a potential vendor treats ‘efficiency’ as just a nice descriptive word or as something that it drives to improve. Platitudes are not enough-ensure you get specifics, including a method of measurement. Ask what detailed efficiency attributes the vendor has implemented and probe to find which of those the vendor have actually developed-as opposed to merely integrating features available to the entire market. This is a good guide as to whether further efficiencies will follow over time.

Use the three main efficiency areas in this paper (environmental, capacity/utilization, and operational) to ensure that any potential vendor is working ‘across the board.’ A ‘checklist’ of specific questions can be created by asking pedantically about each vendor’s abilities to address the attributes and impacts that Compellent offers, and which were laid out in detail on page 3. For example: do they offer thin provisioning? Do they pre-allocate space? How granular and automated is their tiering capability? How do they maintain the performance of highly active data? Of course, get references that include measured real world results. Finally, check that the vendor is practicing what it preaches. For instance, in this respect, Compellent uses all its own products as advertised (you might be surprised how many vendors do not do so) and is also ‘walking the talk’ in efficiency efforts across its own business-both those that promote better business (after all lower costs can mean better margins) as well as more altruistic ones.

The Bottom Line

To repeat a key point: ‘efficient’ is a relative, not an absolute, descriptor. As such, it is prone to the downfall of many a generic word: overuse. It is an easy word to throw around, but hard to genuinely do something about. Compellent has been built on ‘doing something about it’ and the fact that, in today’s economy, ‘storage efficiency’ is enjoying extreme focus might draw some to conclude that Compellent is simply riding the wave along with many others. Nothing could be further from the truth. Compellent has been urging users ‘to buy less storage and to use it better’ since its inception. Of course, (and here there is a delightful irony) the last sentence is itself another relative statement-certainly Compellent wants users to buy absolutely less storage, but relatively more of it from Compellent!

Ending up with less hardware, with more of it being the optimum type, and ensuring it is all well used, has not been a lead rallying cry of storage vendors for that long. Compellent can afford to shout the approach not only because it has the wherewithal to deliver on the claim, but also because it is not yet a major market incumbent. Using 40%, 60%, or 80% less than traditional methods is an effective net loss to old, better-established suppliers, but the remaining percentage is all net new gain to Compellent. It would be interesting to see how Compellent might change its marketing message should it achieve a leadership position in market share-while that is a problem it would no doubt like to have, for now, the firm is comfortable to focus a very bright light on the relative [in]efficiencies found within large parts of the storage market, knowing full well that it shines in this regard, by delivering-whether measured absolutely or relatively-extremely efficient storage.

[2] See: ESG Brief, A Compelling Green Message, April 2008.

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