IBM Systems and Technology August 2011Thought Leadership White PaperDriving down power consumptionwith the IBM XIV Storage SystemFrom architecture to components, storage that’s designed to be green
2 Driving down power consumption with the IBM XIV Storage SystemExecutive summary This paper illustrates how XIV storage architecture isIn recent decades, as organizations have dramatically expanded designed to be green and eco-friendly. Equally important,their data centers, corporate IT energy demands and costs have it shows how the system can reduce power consumption byrisen in lockstep. Data center energy consumption is growing at more than 65 percent compared to comparable storage systems.about 12 percent a year—and is expected to double in the nextﬁve years.1 And data centers can be inefficient energy users. Energy costs and data volumes spur needThe U.S. Department of Energy estimates that most data for efficiencycenters can readily achieve 20 - 40 percent savings in energy The IT revolution has been accompanied by a dramatic rate ofconsumption—and that aggressive measures can achieve better data center growth. The proliferation of data centers has been sothan 50 percent savings.1 Meanwhile, enterprise data is growing striking, in fact, that it is estimated that data centers alone nowat up to 50 percent a year,2 and storage capacity shipments are consume more than 2 percent of electric power in the US3 andgrowing rapidly to meet that demand. With storage equipment 0.5 percent of electricity globally.4 Furthermore, as shown inshowing a high annual growth rate for energy demand, enter- Figure 1, the US Environmental Protection Agency (EPA)prise storage has become a prime driver of data center energy estimated that data center energy consumption was to haveconsumption. doubled between 2006 - 2011.5These facts, along with increasing electricity costs, mandate theimportant role for corporate IT of curbing an organization’spower and cooling costs. Energy efficiency as a result has Figure 1: US data center electricitybecome a key consideration in evaluating storage systems. consumption, 2000-2011 Annual electricity use (billion kWh/year)The architectural rigidity of traditional storage systems, Historical Energy use energy use projectionshowever, tends to result in high energy use. The need to accom-modate future capacity, for example, often necessitates theacquisition of more capacity and hardware than an organizationrequires at the time of purchase. Ultimately, this over-capacitycan lead to higher power costs.The IBM® XIV® Storage System is a high-end storage system,designed to optimize the utilization of storage capacity whileproviding consistent high performance. The many “green”characteristics of the XIV system are designed to help companiesdramatically lower power consumption and energy costs whilemeeting business needs. The amount of electricity used in data centers is on a steep increase, prompting the need to enhance the efficiency of IT hardware such as data storage systems.5
IBM Systems and Technology 3Today, CIOs and IT management understand that keeping Complicating matters, most traditional storage systems consumeenergy costs in check is an important component of their jobs. signiﬁcant amounts of energy due to architectural limitations.This energy imperative is particularly challenging given that Particularly challenging from an energy efficiency standpoint,they must grapple with two near certainties of doing business the design of most traditional systems does not focus on opti-today: the continued growth of their organization’s data capacity mizing capacity utilization. Consequently, companies typicallyneeds and an expected increase of 50 percent in electricity costs purchase more hardware than they need, powering and coolingthrough 2035.6 orphaned or unused capacity. This results in higher power costs.In light of increases in data volumes, rising energy costs and Today’s situation compels IT vendors and customers to face arising energy consumption—and their occurrence in a challeng- stark reality and address a formidable challenge: IT hardware ining business environment—using energy more efficiently makes general and storage equipment in particular must be designedsimple business sense. Energy-efficient companies can reduce with energy efficiency in mind. At the same time, performancebusiness risk, lower electricity bills, reduce carbon emissions and and reliability must continuously improve.demonstrate environmental responsibility. IBM has demonstrated its ongoing commitment to fusingThe role of storage in rising energy use technology with sustainability and the environment, amongand cost other activities, by launching Project Big Green and becoming aThe high growth rate in data center electricity consumption is member on the board of the Green Grid to promote green datadue in no small part to continuously growing demand for enter- centers. IBM’s Smarter Planet initiative focuses on optimizingprise storage, making it increasingly clear that companies must the use of instrumented, interconnected and intelligent IT andexplore new approaches to maximize energy efficiency. Meeting business capabilities worldwide. Designed to be green to thegrowing storage needs by simply adding another rack is, there- core, the XIV Storage System also embodies IBM’s commitmentfore, no longer the answer. Dense drives, reduced footprints and to the environment. Its beneﬁts are two-fold: users can saveinnovative advanced functions—all are required to meet today’s more than 65 percent on power and cooling costs and harnessdemand for energy efficient storage. the power of high-end enterprise storage that delivers high performance and reliability.
4 Driving down power consumption with the IBM XIV Storage System ArchitectureIBM: Helping build a greener world The overriding principle for achieving an energy efficient storage system is to optimize storage capacity utilization, thusIBM is on the forefront of creating more energy efficient minimizing the amount of hardware necessary to provide usabledata centers, launching Project Big Green and leading the storage capacity. The direct result of capacity optimization isway as a board member of the Green Grid, both of which lower energy costs.are dedicated to promoting greener data centers. Otherenergy-related activities include EPA Energy Star-compliantservers and storage, carbon footprint consulting and Minimizing the hardware footprint required to deliver theenvironmental information management. necessary usable capacity can be achieved through architecture design considerations including:A recognized leader for its work in sustainability, IBM hasreceived many awards and widespread recognition for its G Eliminating orphaned space: Over time, 9 to 15 percent ofenvironmental efforts including: most storage systems become unusable and “orphaned” forG 2010: Two Most Valuable Pollution Prevention Awards from various reasons.7 Eliminating this phenomenon can immedi- the National Pollution Prevention Roundtable ately reclaim a large amount of storage for use.G 2010: Ranked #1 on Global 100 of Newsweek magazine’s G Providing thin provisioning: By deﬁning virtual volumes “Green Rankings” of high capacity and using thin provisioning to map thoseG 2009/08: Ranked #1 IDG/Computerworld’s annual Top volumes to less physical space, storage administrators can pur- Green-IT vendors ranking chase the capacity they need today, not an estimated capacity they might need in the future. Storage may be added in the future on a just-in-time basis.Creating the ultimate green storage G Utilizing differential backups: With differential backups, only data that has changed is backed up. Conventional fullsystem backup processes store volumes in their entirety, even if dataImagine that a designer was tasked with creating a high-end has not changed or there is no actual data in the volumes.enterprise storage system with two primary goals: energyefficiency and high performance. How would the designer Experience shows that organizations can signiﬁcantly reduce theachieve these ostensibly opposed goals? amount of storage overhead by integrating the above features, leading to signiﬁcant cost savings in power and cooling costs.Conceptually, the storage system designer needs to optimizestorage capacity utilization. There are two elements withwhich this may be achieved: system architecture and systemcomponents. The resulting design concept would probablylook like this:
IBM Systems and Technology 5ComponentsAs for the physical components that make up the energy efficientsystem, the design can take one of two paths: developing propri- “ IBM XIV storage is giving us greater poweretary, unique components optimized for a storage system or uti- densities, reducing the environmental andlizing off-the-shelf commodity components. In terms of energyefficiency as well as performance, commodity components are overall operational cost of delivering thethe hands down winner. This is due to the following advantages: same amount of storage.”G Leveraging advances in energy efficiency: Disk drive and —Managed service provider, U.S. processor companies are continuously improving the energy efficiency of their products. When designing a system, it makes sense to capitalize on these advances as they are released on the market. Currently, very high density disks are the drives Letting the numbers do the talking of choice for efficiency. In the future, new technologies that Before presenting the IBM XIV system design and architecture provide higher energy efficiency can be integrated into the in detail, it would be useful to examine how its design affects system. bottom line energy costs. The following sections contrast theG Providing higher performance: Just as efficiency is improv- XIV system’s energy consumption to that of two comparable sys- ing, disk drive and processor companies are also enhancing the tems, the EMC Symmetrix DMX-4 and EMC Symmetrix performance of their components. By utilizing off-the-shelf VMAX. The EMC systems are similar to XIV systems in terms components, a system can beneﬁt from the latest research of usable capacity, performance, availability and feature sets. and development in component performance and energy Both EMC systems were compared to second generation and efficiency. Gen3 conﬁgurations of the IBM XIV Storage System.IBM has designed the XIV Storage System using the approach The XIV Storage System versus EMC Symmetrix DMX-4described above. Combining the best of architecture and The ﬁrst comparison places Gen3 and second generation conﬁg-commodity components, XIV storage is a high-end, high urations of the IBM XIV system—each with a usable capacityperformance, energy efficient solution. When it comes to of 111 TB—against an EMC Symmetrix DMX-4 system withenergy efficiency, XIV’s value proposition is simple: IBM allowscompanies to focus on their business at lower energy costs.
6 Driving down power consumption with the IBM XIV Storage System109 TB of usable capacity8. The XIV systems are based on 2 TBSAS (Gen3) and 2 TB SATA (second generation) disk drives,while the DMX-4 system uses 450 GB Fibre Channel drives. All “ We were pushing against the limits of ourthree systems offer comparable performance and features. data center in terms of power and space. TheThe results are eye-opening. The Gen3 and second generation XIV system gave us back some much-neededXIV systems consume 67.9 percent and 62.5 percent less power, headroom … [and] on the ﬁnancial side, werespectively, than the EMC DMX-4 system. save 50,000 Australian dollars a year in electricity costs.” Figure 2: IBM XIV vs. EMC Symmetrix DMX-4 —Government agency, Australia. XIV Storage System versus EMC Symmetrix VMAX In this comparison, Gen3 and second generation XIV systems— each with a usable capacity of 222 TB—are benchmarked against an EMC Symmetrix VMAX system with a usable capacity of 212 TB9. The XIV systems are based on 2 TB SAS for Gen3 and 2 TB SATA disk drives for second generation, while the VMAX system uses 600 GB Fibre Channel drives. In this case, the Gen3 and second generation conﬁgurations of IBM XIV Gen 3 IBM XIV second generation EMC DMX-4 the XIV system use 34.5 percent and 23.4 percent less power, kVA TB / kVA respectively, than the EMC VMAX system.
IBM Systems and Technology 7 Figure 3: IBM XIV vs. EMC Symmetrix VMAX “ The XIV system uses 50 percent less power than the previous SAN system.” —City government agency, U.S. Reclaimed orphaned capacity One of the drawbacks of most enterprise storage systems is that, over time, an average of 9 to 15 percent of capacity becomes lost and unusable. The complexity of volume management, volume striping for performance and the ever-changing nature of IBM XIV Gen 3 IBM XIV second generation EMC VMAX applications in an enterprise environment lead to the presence of idle storage chunks. Known as “orphaned” space, these chunks kVA TB / kVA can be reclaimed in traditional storage systems only through tedious system restructuring, a process that can be more expensive than buying additional storage.The IBM XIV Storage System: The XIV Storage System automates much of the storageGreen by design management process, rendering obsolete the common tasks ofThe IBM XIV Storage System is green by design, not by after- striping and migrating or reallocating resources. The system isthought. Unlike most competing systems, the XIV Storage kept at a balance that maximizes the performance of all volumesSystem has been designed to optimize capacity utilization. The and utilizes all disks evenly. Deﬁning new volumes, resizingfollowing sections describe how optimization is achieved existing volumes, adding more capacity and even phasing out oldthrough the combination of architecture and components hardware are all handled seamlessly by the XIV system, withoutspeciﬁcally designed to lower energy costs. administrative effort. The system is designed to ensure that no space is lost, there are no hotspots and energy is not wasted on unutilized, orphaned capacity.
8 Driving down power consumption with the IBM XIV Storage SystemDifferential backups/snapshots Actual energy savings generated by thin provisioning depends onThe ability to create periodic backups of entire volumes is various factors. Among them are enterprise applications’ dataessential to any enterprise storage system. Backups are required growth rate and a company’s implementation standards. It isto maintain regulatory compliance, access older data, and restore IBM’s experience that when measured over three years, thedata upon failure or human error. With traditional enterprise XIV system can save as much up to 45 percent on capacitysystems, however, backup and restore processes can be costly. compared to a similar system without thin provisioning. Once again, lower capacity translates into lower energy consumptionTraditional backup processes involve writing full volumes of data and costs.onto additional unused storage space. This includes copyingunused space that has never been written to and should not becopied. XIV storage handles backup with differential backups Figure 4: Capacity utilizationand snapshots, copying only the blocks of data that have actuallybeen written. It does not copy unwritten or “zero” data. Incontrast to legacy systems, which require higher rates of unusedspace, the XIV approach greatly reduces the capacity, time andcost necessary for backups. Implementations of XIV StorageSystems, in fact, have experienced reductions in storage capacityrequirements as great as 15 to 30 percent, thus reducing energyconsumption.Built-in thin provisioningThe XIV Storage System includes thin provisioning as a corefeature of its design, managed at the click of a button. Thinprovisioning provides the ability to deﬁne a system’s logicalcapacity as larger than its physical capacity. This enables compa- Traditional Tier-1 system IBM XIV systemnies to defer physical capacity purchases and acquire physical Lost Full Thick Effectivecapacity solely for the total space actually written rather than the space snapshots provisioning capacitytotal space allocated. While it is true that most enterprise storagesolutions offer thin provisioning, in many systems this feature isadded to existing architectures, making it harder to manage and Thick to thin allocationof limited scope. With the XIV system, thin provisioning is Organizations choosing to switch from a legacy storage systemincorporated from the beginning as a fully integrated system to XIV storage can seamlessly beneﬁt from the system’s thincomponent. allocation features. When a thickly provisioned volume is migrated from a legacy system, the XIV system’s thin provision- ing mechanism will not allocate any unused space. Instead, it can
IBM Systems and Technology 9shrink existing volumes upon migration by copying only con- Automatic load balancing and self-healingsumed blocks of storage. With XIV storage, capacity is not used System load balancing and self-healing enable XIV storage tountil it is required. This results in higher capacity utilization and provide Tier-1, enterprise-level performance while using fewerlower energy requirements. drives. By using fewer drives for a given capacity, XIV storage consumes less electricity and can provide better performanceInstant space reclamation than that of traditional systems through the use uniqueThe XIV Storage System offers the capability of reclaiming data algorithms and data distribution.that was previously in use but is now out of use. When applica-tions are logically formatting areas of the volume, the formatted Single-tier architecturecapacity is reassigned to another volume. The system performs Most IT organizations use practices such as information lifecyclespace reclamation automatically and offers easy management management (ILM) to reduce costs. These efforts involve multi-tools for leveraging this capability to the fullest. Instant space tiering, however, which adds a substantial degree of complexityreclamation allows XIV users to optimize capacity utilization. It and cost to system management. A multitier storage solutioncan reduce costs by enabling supporting applications to instantly typically involves a number of different architectures, eachregain unused ﬁle system space in thin-provisioned volumes. requiring a different level of expertise to manage. Moving the data between tiers requires effort and planning and involvesThe XIV Storage System supports Symantec’s Storage hardware and operating expenses for each tier. As each environ-Foundation Thin Reclamation API. The Symantec API inter- ment grows, equipment must be added to one tier or another.locks with the XIV system to instantly detect unused space and Since this growth is typically unpredictable, acquisitions areautomatically and immediately reassign the space to the general often not cost efficient.storage pool as unused capacity. This is a tight integration pointwith thin-provisioning-aware Veritas File System (VxFS) by The single-tier XIV architecture can eliminate the complexitySymantec. It ultimately enables companies to leverage the thin- and cost of migrating data from tier to tier. It also can reduce theprovisioning-awareness of the XIV Storage System to attain complexity of maintaining different architectures for differenthigher savings in storage utilization with Symantec ﬁle systems. tiers of storage. From the standpoint of energy efficiency, it enables scaling of components—including capacity, interfaces,More information on space reclamation is available in the cache, CPU power and internal bandwidth—on the same plat-IBM XIV thin reclamation white paper. form. As a result, less hardware is required with the XIV system to achieve the same usable capacity. This combination provides the ability to dramatically cut energy costs.
10 Driving down power consumption with the IBM XIV Storage System Components advantage: Very high XIV power: Designed for high-end density hard drives enterprise storage The XIV Storage System can minimize costs and provide Just as its storage architecture can directly reduce energy needs exceptional ﬂexibility by treating hardware as an interchangeable and expenditures, the XIV system’s electric power design can commodity. Based on off-the-shelf hardware components, lower costs in an indirect yet signiﬁcant manner. Designed for XIV storage is designed to integrate the latest disks, modules, enterprise-grade storage, the XIV system includes the following interconnects and other components, enabling organizations to features to protect against electricity provisioning problems: capitalize on market advances in capacity, cost and energy efficiency while meeting their dynamic performance and budget G Power feed redundancy: XIV storage plugs into two requirements. different power grids, assuring redundancy in the case of power outages. XIV storage utilizes very high density hard drives to drive down G Automatic transfer switch (ATS): The ATS provides seam- energy costs. Leveraging the energy and capacity advances of less failover from primary to a secondary or tertiary source and off-the-shelf high density drives enables the XIV system to pro- back. This is especially important for switching to a backup vide more storage with signiﬁcantly lower energy consumption power source for the provisioning of temporary electric power. per capacity unit. Future growth in drive capacities can result in G UPS system: The UPS system sustains system power corresponding savings in energy use and cost. redundancy in the event that one power grid fails. G Power monitoring: The XIV system user interface includes power monitoring capabilities in which each power compo- nent and element can be monitored separately. Administrators“ One of the targets that we have … is to save can also deﬁne alarms, warnings and alerts in case of power energy and ﬂoor space … In the consolidated issues, spikes and other issues. space we are being more efficient in a smaller footprint. Right now in the computer center we are running in one rack what we used to have in ﬁve different racks.” —Insurance company, Puerto Rico
IBM Systems and Technology 11 industry leading energy efficiency. The XIV Storage System has shown that combining innovative architecture with commodity components can reduce storage energy costs by more than 65 percent when compared to competing systems. As data growth rates and energy prices increase, companies must identify IT solutions that reduce energy consumption without compromising performance, features or reliability. Designed to be green, the XIV Storage System is such a solution. It can play an important role in helping your company achieve its energy- efficiency requirements. For more information To learn more about IBM XIV Storage Systems, please contact your IBM marketing representative or IBM Business Partner or visit: ibm.com/systems/storage/disk/xivA graphical interface simpliﬁes management of system components withpoint-and-click checks, including for power status. Additionally, ﬁnancing solutions from IBM Global Financing can enable effective cash management, protection from technol- ogy obsolescence, improved total cost of ownership and returnConclusion on investment. Also, our Global Asset Recovery Services helpThe XIV Storage System is a high-end data storage system address environmental concerns with new, more energy-efficientoffering numerous advanced features and documented beneﬁts solutions. For more information on IBM Global Financing, visit:to enterprise organizations. One of the primary beneﬁts is its ibm.com/ﬁnancing