How To Calculate Hd Costs

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1 Total Cost of Ownership Comparison of PCs With Hosted Virtual Desktops, 2011 Update Gartner RAS Core Research Note G , Federica Troni, Mark A. Margevicius, Michael A. Silver, 14 December 2010, RA Hosted virtual desktops (HVDs) bring the benefits of centralized architecture with improved operational efficiency. Total cost of ownership (TCO) savings exist, but these alone are not sufficient to justify a migration, as a high level of initial capital investments is required to build the back-end infrastructure. Key Findings The TCO of HVDs can range from 2% to 13% lower than comparable desktop deployments. HVD implementation scenarios that use current image management technologies for light desktop application loads have lower or similar direct costs as those of traditional desktop PCs deployments. New server and image management technologies can reduce direct costs up to 15%, and can lower the overall TCO of HVDs by 9 to 12%, as compared with older-generation HVD deployments. Dedicated and pooled image implementations will increasingly be replaced by dynamic image implementations. Recommendations Use HVD migrations as opportunities to move to higher levels of management and gain more flexibility at lower or similar direct costs. Ensure that all HVD business cases include TCO considerations, as well as benefits that are more difficult to quantify, such as the ability to give secure access to applications and data to remote users, the ability to accommodate a broader choice of client devices, and increased security and manageability. Select dynamic image implementations for light loads over pooled image deployment, as the TCO for dynamic images is up to 11% lower. Choose dynamic images augmented with persistent personalization software instead of dedicated implementation when personalization is required, as the TCO of dynamic images is 9% to 12% lower than that of dedicated image implementations.

2 2 ANALYSIS An HVD is a full, thick-client user environment, which is run as a virtual machine (VM) on a server and accessed remotely. HVD implementations comprise server virtualization software to host desktop software (as a server workload), brokering/ session management software to connect users to their desktop environments, and tools for managing the provisioning and maintenance (e.g., updates and patches) of the virtual desktop software stack. The advantages of this client architecture are that it allows centralized management of applications and data, higher security and speed of provisioning. It is also a viable option to securely deliver applications to remote users and a variety of client devices. The TCO benefits of HVDs, however, have been in doubt in the past, as reductions in IT labor and end-user costs were often offset by the capital costs required to build the required back-end infrastructure. Since the publication of our first research on the TCO of firstgeneration HVDs in 2008, the technology has evolved in many respects. In this update, we will account for several technology changes that have resulted in new implementation scenarios and different back-end infrastructure requirements. Three Implementation Scenarios HVDs can be deployed in different ways to accommodate the requirements of different users and organizations. The various implementation options have different TCO implications. Some of the scenarios described below employ the latest generation of HVD software; others are legacy scenarios that are still deployed by some organizations. Going forward, the dedicated and pooled image scenarios will gradually be replaced by newer, dynamic image scenarios: Implementation of dynamically built images: In this scenario, one copy of the OS is stored in the data center and will serve multiple user images. Images are composed dynamically when users log on, by combining the OS with the appropriate set of applications. This is achieved with different technologies by different HVD software vendors, but leads to similar results. The main advantage of this implementation scenario over the other two is that it substantially reduces storage requirements and simplifies management of the OS. Different degrees of personalization of the desktop are available for these scenarios today; however, for advanced features, third-party tools are required.third-party tools may be required to go beyond basic settings and folder/file redirection. Implementation of pooled images: In this scenario, we simulate a deployment of generic, fully locked-down images, where no deduplication technology is used. No image deduplication technology is used. Users will connect to the first available VM as they log on, and the image is taken back to its pristine state when the user has finished using it. This scenario is less complex, from a management perspective, than the one above, but it is suitable only for niche groups of users. Implementation of dedicated images: In this scenario, users are associated with their own, unique HVD image. No image deduplication technology is used and the user image is exactly as it was on physical PC, but it is now placed in a VM and runs on a server in the data center. Each image includes a full copy of the OS, applications and user s personal data. Dedicated images represented one of the first HVD deployment methods. The advantage of this option is that it can accommodate users that require full personalization of the desktop. The disadvantage is that it is typically also the most expensive scenario, as it requires a large infrastructure build out; and, unlike other scenarios, it does not help organizations introduce higher levels of manageability for their client-computing deployments. Heavy Versus Light Loads We have calculated the TCO for these implementation scenarios comparing different infrastructure set ups serving different clientcomputing workloads. Heavy load scenarios represent HVD deployments for demanding or sophisticated users, which will require high numbers of applications and large amounts of data. Light load scenarios, conversely, represent implementations for users requiring fewer applications to do their job and store limited data. The distinction between heavy and light loads impacts the infrastructure requirements, as it affects memory and storage requirements, as well as the user-to-server ratio. What s New Several items have changed from the 2008 update: Hardware, software and facilities: In this update, we have included a lower thin-client cost. The per-server costs have more than doubled, as compared with the 2008 numbers since we now include dual-cpu, quad-core and dual-cpu, sixcore servers with 96GB and 128GB of memory, respectively. This cost is partly compensated for by the higher density of users per server that is currently achievable. We have lowered the per-user software costs, which are now set at $750, 2010 Gartner, Inc. and/or its affiliates. All rights reserved. Gartner is a registered trademark of Gartner, Inc. or its affiliates. This publication may not be reproduced or distributed in any form without Gartner s prior written permission. The information contained in this publication has been obtained from sources believed to be reliable. Gartner disclaims all warranties as to the accuracy, completeness or adequacy of such information and shall have no liability for errors, omissions or inadequacies in such information. This publication consists of the opinions of Gartner s research organization and should not be construed as statements of fact. The opinions expressed herein are subject to change without notice. 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3 including annual maintenance, but we have included a higher, more-realistic cost for the HVD software. In the first scenario, we present costs for a Windows XP and a Windows 7 HVD deployment; other scenarios are Windows 7-based. We now include electricity costs for thin clients and servers. IT operations: We have increased salaries by 6%. For managed scenarios, we now include the labor costs for the personnel required to operate management tools. Administration: Under administration, we account for storage allocation, an element that we have revised and increased substantially, per Gartner s client feedback. We now also account for storage management, a cost item that was not included in our previous analysis. End-user costs: We have increased end-user salaries by 6%. Many of the changes we have implemented in this update are the direct consequence of the feedback of Garner clients engaged in pilots and live deployments, and go in the direction of increasing TCO. Indisputable TCO benefits, due to new image management and server technologies, are partly offset by the changes we have implemented in this update. Assumptions Common to All Scenarios Note 1. Thin-Client Versus Repurposed PCs for HVD Deployments Several organizations use repurposed PCs for their HVD deployments; by doing, so they lower initial capital investments, However, they suffer higher energy costs and potentially higher IT operations costs, as PCs have a full OS to manage and secure, and more parts that can potentially fail. We build scenarios for a 2,500-user deployment, where the endpoint device is a thin client priced at $350, without considering volume discounts (see Note 1). Thin clients have a life cycle of six years and four years for servers. For the purpose of this research, we assume a mix of 50% data entry users (using one or two applications to do their job) and 50% task-oriented workers (using a small set of applications and operating within a known set of functions). The user mix impacts mostly end-user costs, as these are determined using the average salaries, but also the application mix and the help desk figures. Networking costs are not included in our model, as they vary too widely from organization to organization. Our model organization has only one large central location, and the HVDs are all hosted in one data center. Moredispersed organizations may have significantly different costs for improved network communications. Costs are presented per user, per year. Each user has a cost allocation for software that includes an office suite, and calendaring, and business applications. On top of this, we allocate $180 per user for the perpetual license of HVD software, plus $30 per user, per year for maintenance. We assume no Software Assurance, so we have included a Microsoft Virtual Desktop Access (VDA) license at $100 per user, per year. When appropriate these costs, we present TCO numbers for the following four scenarios, which assume different levels of manageability: Unmanaged: Users can install applications and change settings; little to no management tools are being used. Moderately managed: There are tools and good processes and policies in place; users can install software and change at least some settings. Locked and well-managed: There are tools, processes and policies in place; users cannot install software or change critical settings. In managed scenarios, we include the cost of servers to run the management tools and labor costs for the technicians required to use the tools. Scenario 1: Dynamic Images, Light Loads In this scenario, we simulate the use of current-generation HVD software that dynamically assembles the image for users. In Columns 2 and 3, we assume that 35-blade dual-cpu quad-core Xeon X5550 servers with 96GB of memory priced at $13,350 each and two chassis that can accommodate 16 blades each, priced at $2,700 each, will be used to accommodate our model deployment of 2,500 users. No volume discount is taken into consideration. We assume the virtualization of nine users per core, i.e., up to 80 users per server. In the Columns 4 and 5, we assume the use of 24-blade, dual- CPU six-core Xeon E7540 servers with 128GB memory priced at $15,100 each and two chassis. Again, we assume the virtualization of nine users per core; i.e., up to 108 per server. We allocate 1GB of storage for data per user for Windows XP scenarios, and 1.5GB per user in Windows 7 scenarios (for storage costs, see Note 2). This scenario is a de facto locked-down scenario. Figure 1 illustrates the TCO for this scenario, and compares it to a traditional locked and well-managed desktop deployment (for other desktop TCO scenarios, see Note 3). 3

4 4 Figure 1. Dynamic HVD Deployment, Light Load In this scenario, the TCO of HVDs is 9% to 10% lower than those of well-managed and locked-down PCs. Direct costs are 4% to 6% lower than those of traditional desktops. Savings are in the area of IT operations administration and end-user costs. Compared with the pooled image scenario described in Scenario 3, a dynamic image scenario with light loads is 11% to 12% less expensive to run overall, and has 13% to 15% lower direct costs. Capital costs are 7% to 9% lower than those of a pooled image scenario. Scenario 2: Dynamic Images, Heavy Loads In this scenario, we again assume the use of current-generation HVD software that dynamically assembles the image for users; this time, however, we are hosting heavy desktop application loads. In Columns 2, 4 and 6, we assume that 45-blade, dual-cpu quadcore Xeon X5550 servers with 96GB memory priced at $13,350 each, fitted in three chassis priced at $2,700 each, will be used to accommodate the 2,500 users. Again, no volume discount is taken into consideration.

5 5 In Columns 3, 4 and 7, we assume the use of 30-blade, dualcpu six-core Xeon E7540 servers with 128GB memory priced at $15,100 each and four chassis. Again, we assume the virtualization of seven users per core. We allocate 14.85GB of storage for data per user for a Windows 7 scenario. Figure 2. Dynamic HVD Deployment, Heavy Load In this scenario, we simulate some degrees of desktop personalization, so we add to software costs an amount for persistent personalization software ($25 for a perpetual license) and for an annual maintenance fee ($5). Figure 2 illustrates the TCO for this scenario.

6 6 In this scenario, the TCO of HVDs is 15% to 6% lower than that of well-managed and lockeddown PCs. Direct costs are lower or comparable to those of the traditional desktop deployment in all scenarios. It should be noted, however, that a HVD scenario that also uses persistent personalization software is more flexible than a well-managed and locked-down PC, as it allows for some degrees of desktop customization. For this scenario, we have presented a Windows 7 deployment. For a Windows XP deployment, we would define 13.2GB as the storage allocation for each user. This would reflect in an 11% lower storage cost and a 0.4% decrease in direct costs. Figure 3. HVDs Pooled Images, Light Loads Scenario 3: Pooled Images, Light Loads Figure 3 presents the TCO for a pooled image implementation for light loads. This time, we assume that 35-blade, dual-cpu quad-core Xeon X5550 servers with 96GB memory priced at $13,350 each, fitted in two chassis priced at $2,700 each will be used to accommodate 2,500 users. Again, no volume discount is taken into consideration. We assume the virtualization of nine users per core; i.e., up to 72 users per server. Allocated to each user for a Windows 7 deployment is 15GB of storage. In this scenario, the TCO for HVDs is comparable to that of a well-managed and locked-down desktop scenario. The direct costs and capital costs for HVDs are, however, 11% and 16% higher, respectively. An equivalent HVD deployment with Windows XP instead of Windows 7 would have 34% lower storage costs and 1% lower overall direct costs. Scenario 4: Dedicated Images, Heavy Loads Figure 4 presents the TCO for a dedicated image implementation for heavy loads. Specific assumptions for this scenario include 45-blade, dual-cpu quad-core Xeon X5550 servers with 96GB memory priced at $13,350 each and three chassis that can accommodate 16 blades each, priced at $2,700 each. We assume the virtualization of seven users per core; i.e., 56 users per server. Each user will have 45GB of storage for a Windows 7 deployment. Compared with a traditional distributed desktop scenario, the HVD implementation with dedicated images for heavy loads still has direct costs that are 8% to 13% higher. The overall TCO of HVDs is lower in unmanaged and moderately managed scenarios, due to significantly lower end-user costs in all HVD scenarios. An equivalent HVD deployment with Windows XP instead of Windows 7 would have 11% lower storage costs and 1% lower overall direct costs.

7 7 Figure 4. HVDs Dedicated Image Implementation, Heavy Loads

8 8 Note 2. Storage Costs Figure 5. Costs and Volume Discounts for Storage Figure 5 summarizes the costs and volume discounts for storage. Note 3. Desktop PC TCO Figure 6 represents the desktop TCO used for comparison with the HVD TCO scenario. These differ from the figures published in Research Desktop Total Cost of Ownership: 2011 Update as they are calculated using the same user mix as the one used in the HVD scenarios in this research; i.e., 50% data entry and 50% task-oriented workers. Figure 6. Desktop PCs TCO