X-Pod for VDI Reference Architecture Enabled by Cisco UCS, VMware Horizon View, and ISE 740 Hybrid...

Validated Reference Architecture August 2014

X-Pod for VDI Providing a simple yet best of breed converged

infrastructure for virtualized desktop solutions

Enabled by:

X-IO ISE 740 Hybrid Storage Array

VMware Horizon View 5.3

Cisco UCS

X-Pod for Horizon View 5.3 2

Table of Contents

Introduction..................................................................................................... 3

Key takeaway ...................................................................................................................................... 3

Executive Overview.......................................................................................... 3

Why VDI? ............................................................................................................................................ 4

VDI—Business Benefits ................................................................................... 5

Flexible Desktop Environment .............................................................................................................. 5

Better, Easier Desktop Management .................................................................................................... 5

De sktop by Template ........................................................................................................................... 6

Security and Compliance ..................................................................................................................... 6

BYOD Support ..................................................................................................................................... 6

Virtual Desktop Implementation Risks ............................................................... 7

Performance & Capacity: Not a Trade-Off ............................................................................................ 7

Reliability and Redundancy .................................................................................................................. 7

Deploying and Expanding Desktop s Pools ........................................................................................... 8

Redefining “Steady-State” Operations .................................................................................................. 8

VDI Planning Questions to Ask ......................................................................... 9

Solution Overview...........................................................................................10

Components ...................................................................................................................................... 10

Solution Architecture ......................................................................................13

Hardware Components ...................................................................................................................... 14

Software Components........................................................................................................................ 15

Cisco Unified Compute System (UCS) ............................................................................................... 15

VMware vSphere 5 ............................................................................................................................ 16

VMware Horizon View 5 Environment Architecture ............................................................................. 18

VMware vCenter Operations Manager................................................................................................ 21

X-IO ISE 740 Hybrid Storage Array .................................................................................................... 22

Performance Analysis of Tested configurations ................................................23

Test Methodology .............................................................................................................................. 23

Workload Analysis ............................................................................................................................. 23

Virtual Desktop Deploy Operations..................................................................................................... 27

Virtual Desktop Boot Storm ................................................................................................................ 29

Conclusion .....................................................................................................31

Contact X-IO technologies ................................................................................................................. 31

Appendix........................................................................................................32

Appendix A: Detailed Analysis of vSphere Performance Graphs, Login VSI 500 User Run ................ 32

Appendix B: EXAMPLE Login VSI Target Desktop Pool Configuration................................................ 33


Introduction

This white paper provides a primer for the X-Pod for VDI converged infrastructure solution, powered by X-

IO storage. X-Pod is a reference architecture designed to deliver a repeatable, high -performance virtual

desktop infrastructure. It util izes an industry-leading VMware Horizon View 5.3.1 environment, hosted on

Cisco Unified Computing System (UCS) Blade Servers, with storage housed on a single, high -

performance, X-IO ISE 740 Hybrid Storage Array.

The environment described herein has been extensively tested by X -IO and verified by VMware. This

document is intended to provide insight into the components, the architecture , and the performance

required to meet the demands of a 500, 1000, and 1500 seat virtual desktop infrastructure (VDI)

deployment.

Key takeaway

This paper details the extensive testing that X-IO has performed and

provides guidance as to the performance requirements of various

operations based on the X-Pod core components of Cisco UCS server and

networking hardware together with the X-IO Intell igent Storage Element

(ISE) systems. This validated testing demonstrates that this solution is

capable of delivering a high-performance desktop experience at up to 97%

concurrency.

It is designed to act as both a primer for VDI deployments and as a

technical overview of the X-Pod architecture. Those readers who are

comfortable with the business and technical benefits of deploying VDI

together with the pitfalls of implementing such an infrastructure should

progress to the Solution Overview section of this document.

Executive Overview

When discussing VDI architectures with customers and solution providers, X-IO have noticed a common

trend of two concerns. Firstly whether the technical statistics and benchmarks provide are “real -world” or

marketing-hyped numbers. Secondly whether VDI architects should be util izing hyper-converged systems

or using best of breed components. It is therefore worth briefly covering these points in turn.

When it comes to VDI design, there are many pitfalls that can occur. This has led to a frightening statistic

that for every successful VDI implementation, there are 7 to 10 that fail, the vast majority of these being

due to an inappropriate storage design. X-IO have therefore worked with real -world benchmark tools such

as Login VSI to ensure that any benchmarks carried out are true reflections of use r actions rather than

synthetic workloads applied by I/O testing tools. All of the user counts reflected in this document are

actually high-util ization loads and if anything, are worst-case numbers rather than optimistic based upon

assumptions or unrealistic scenarios (e.g. zero user data or ridiculously high data de -duplication

forecasts).

With regards to the argument for hyper-converged systems, the systems out there today undoubtedly

have their place, however they need to be precisely architected for tod ay’s workload and are relatively

inflexible for future growth or change of use. This has often led to a difficult decision for architects as to


whether to endure the complexity and risk of using best of breed components or to compromise and

deploy a pre-converged, collapsed stack. With the arrival of converged solutions such as X -Pod, best of

breed components can be deployed, however using pre -architected and tested blueprints that give the

peace of mind previously only found with hyper-converged systems.

Why VDI?

Virtualization of servers and IT infrastructure has been well established in the business landscape .

Operating expense (OPEX) cost reductions are routine in a virtualized data center due to the reduced

number of physical servers, more centralized management tools, energy savings, and many other factors.

This cost savings makes desktop virtualization such a promising opportunity to transform a major cost for

IT organizations. Unfortunately, virtualized desktop workloads are unlike most of the server virtualization

workloads with which organizations have experience. While “steady -state” desktop operations are what is

commonly sized for (for example, 10-20 IOPS/desktop), it is the “non-standard” operations and

misconfigured sizing operations that eventually cause poor user experience and make VDI such a

challenging, and expensive, solution to design and implement.

By leveraging desktop virtualization solutions such as VMware Horizon View, IT organiza tions can

provide their customers with a superior desktop experience while decreasing management cost and

increasing flexibil ity of the organization. IT organizations can now increase the leverage of their IT staff by

consolidating desktop management and hardware into the enterprise virtualization computing model. For

example, relatively few IT staff can manage hundreds (if not thousands) of desktops for patch

management or application upgrades. Using tools such as VMware Horizon (with View) to manage

snapshots, gold images can be quickly reverted to a known state if required, which reduces capacity as

only data changes are stored for each snapshot. By contrast, traditional methods of patch management

require excessive involvement from the IT organization across hundreds (if not thousands) of physical

machines that could be spread around the world.

In addition to desktop virtualization, tools are now available to virtualize applications as well. End users

can be provisioned individual applications that can be delivered to any device, whether that is a laptop,

tablet, or smartphone. As the “bring your own device” (BYOD) phenomenon continues to grow, users

demand more flexible access to the resources they need to perform their jobs. Policies that prohibit

employees from using personal devices, and that the company does not pay for, are becoming more

difficult to defend.

Implementing a virtual desktop solution can be immensely beneficial to the organization, but if

implemented incorrectly, it can be an equally im pressive failure. User experience is the “gold standard”

that any solution will be held to, because users will evaluate the new solution based on the physical

desktop that was just replaced. Proof of Concept (POC) testing is essential when evaluating any n ew

solution, because the process of configuring the test gives essential information about how the system

will perform. Tools such as Login Virtual Session Indexer (Login VSI™) are critical for simulating “like”

production workloads and are a worthwhile investment as part of evaluating different solutions.

Inadequately designed VDI implementations often perform well in the POC phase but are overwhelmed

when placed into production. In a majority of these cases, storage performance is often the cause of poor

user experience, is the most often undersized for performance, and can be the most expensive single

component of any VDI solution.

http://www.loginvsi.com/


VDI—Business Benefits

Properly sized and implemented, a VDI project can provide users with a “whole” desktop experience that

surpasses their physical desktop machine. However, the benefits to the business are similar to server

virtualization but are applied at an order of magnitude greater scale. Enterprise -class computing hardware

can be applied to end-user computing (reliability/availability/performance) and can leverage large -scale

virtualization management techniques (capacity/scale). This can allow for greater leverage of existing IT

staff, enable higher levels of reliability (including disaster recovery), and reduce overall ongoing costs to

the business.

While VDI can be a tremendous advantage for the business, data storage costs are the single largest

cost component of the solution and the most common cause of poor user experience and failed

implementations. Listed below are some advantages to the business and the role that storage has to play

in each.

Flexible Desktop Environment

Many types of desktop needs are seen across various organizations and industries. Based upon the load

pattern and use case, different kinds of desktop virtualization options are available. In fact, it is l ikely that

multiple types of implementations exist in a single, larger organization.

For example, the resource requirements for graphic designers, software developers, Microsoft Office

power users, and executives are quite different than the requirements for a call center or kiosk desktop.

The power users will generally have higher CPU and memory requirements and will l ikely require that the

desktop be persistent. Power users will expect any changes to their desktop to be preserved and in the

same state they left it when logging off.

In a call center (or kiosk) configuration, users expect to log in to any desktop and have the exact same

experience with nothing preserved on the desktop. If one desktop has an issue, the user simply moves to

another desktop instance and tries again. There is usually a standard suite of software that these virtual

desktops util ize to support the business functions. This is espe cially true if, for example, cloud-based

customer resource management (CRM) service or Office365 are being used.

Better, Easier Desktop Management

With physical desktops, the IT organization has to go out and physically touch each desktop in some

cases to remediate a problem. This geographic dispersion, even if within the same office building,

increases the staffing requirements to manage the end -user desktops and increases the time required for

“break/fix” functions. There is also an increased risk of data theft when users store corporate data on

physical desktops that reside anywhere in the organization. Desktop virtualization allows for centralized

management of the most commonly touched component in the desktop solution, the desktop itself.

Backups can also be more effective, since all user data is kept in the datacenter – even though it looks to

the user like an attached, physical disk housed on local storage. This eliminates many of the issues seen

with trying to back up hundreds and thousands of remote , physical desktop machines. Network

interruptions, issues with individual operating system bugs, fail ing physical hard drives, and so on are all

mitigated by util izing a common storage platform. In addition, since the effective storage for each user

desktop is deduplicated by the VDI layer (VMware View Composer Linked Clones), the amount of storage

actually needing to be backed up is vastly reduced and quickly recovered.

VMware has for years provided a rich API to enable storage partners to better integra te with the VMware

ecosystem. This enables the virtualization administrator (vAdmin) to quickly and efficiently assign storage


resources where required while the complex provisioning of storage resources up through the different

virtualization and hardware layers is done by software. This greatly leverages the amount of storage the

vAdmin can effectively manage and ensures that best practices are followed for storage configuration,

thereby reducing risk.

Desktop by Template

IT organizations can create a library of virtual desktop templates, each of which can be carefully tuned

and configured for the business need. These templates can then be used to provision virtual desktop

machines very, very quickly—in minutes in most cases.

For example, if an organiza tion routinely uses contractors for a few different types of functions, a “gold

image” template can be created for each, which can include the appropriate operating system, security

settings, and all the applications contractors would need to accomplish th eir tasks. When a new contract

employee is added, the IT staff need only deploy a new virtual desktop based upon the appropriate

template. This can be done literally in minutes, but this can also generate an enormous amount of storage

traffic—or I/Os per second (IOPS)—with a relatively small number of deploy operations.

NOTE: Deploying a desktop is one of the most performance-demanding operations that storage will

encounter in a desktop virtualization solution. Performing these operations during “steady -state”

operations can put an abnormally large strain on the storage infrastructure and can impact the user

experience of all other users on the system.

Security and Compliance

VDI allows an IT organization to have much better control over corporate data. As such, it makes the job

of implementing consistent, common security and compliance features easier. Depending upon the

industry the organization is in, compliance and security concerns can be important or strictly mandated.

With physical desktops and mobile devices, corporations face the increased risk of data loss and theft of

any device where data is stored “locally.” Desktop virtualization enables employees to work with data

securely on centralized corporate resources. In some cases, users can work from any device in any

location with their data meeting the security requirements of the organization.

Depending on the role of the desktop users, certain data regulations may apply that require data

separation and isolation (e.g., financial, legal, and medica l). This requires separate storage devices that

must be able to support high IOPS and capacity levels that the separated pools require. Modular -based

storage systems are inherently designed to accommodate this data security requirement.

BYOD Support

Increasingly, organizations are supporting (and are being demanded to support) “bring your own device”

(BYOD) functionality. The workforce is changing, and the growing expectation is that applications and

desktop access will be available on whatever device the employee has, from laptop to tablet to

smartphone. This also has an immense benefit to the business, as the employee is providing a

“preferred” end-point device that can be used to be productive.

VMware Horizon View offers a very rich interface that allows users to access their applications and

desktop on any mobile device. Individual applications can be virtualized, further enabling employee

productivity and easing the demands to corporate computing resources.


Virtual Desktop Implementation Risks

While the list of benefits that can be realized by VDI implementation, both in manpower and in operating

expenses (OPEX), is impressive, the opportunities for failure are equally concerning. This section lists

several areas that can put a VDI initiative at risk. In all cases, sufficient planning for the final production

load and careful monitoring of operations are required to ensure smooth operations.

Performance & Capacity: Not a Trade-Off

Performance has a direct effect on end-user experience, and poor storage performance sizing is usually

the number one reason. Many VDI solutions are sized only for “steady -state” performance requirements.

Common VDI operations, such as boot storms, login storms, deploy operations, recovery, and other

“maintenance operations,” can require an enormous amount of transactional performance (IOPS) from

storage systems. VDI instances have to respond with little or no discernable impact to the end user when

these maintenance operations are conducted.

Performance is not the only thing to consider when sizing a VDI solution, as there must be enough

capacity to satisfy the requirements for user data, operating systems, application data, and user persona.

While there are several techniques to increase the amount of effective capacity a soluti on can provide

(VMware View Composer Linked-Clones), there is stil l an underlying requirement for capacity—

performance. Unlike regular “fi le server” class capacity, this data has performance requirements that go

across all of the data (e.g., there is l ittl e “dead data”). This broad requirement means that while there may

be areas of high-performance concentration (base images or replicas), the rest of the data has a high

IOPS/TB requirement as well. This rest of the data is what the individual VDI instances have to work with,

so any slowdown in capacity will directly affect the end -user experience. Solutions that rely on calculated

deduplication and compression techniques will see degrading performance ratios as the capacity is

consumed, as there are limited amounts of processing power and memory capacity in the storage

controllers (i.e., the number of calculations increases with increasing capacity).

According to VDI support organizations, storage systems account for 80 – 90% of the VDI performance

issues reported. Often this is due to read and write latency in the storage system.

Reliability and Redundancy

No virtualized datacenter is sustainable without reliability and redundancy. In the past, services running in

the data center did not necessarily represent a disaster if there was a service disruption. For example, a

service event to the CRM applications, or email services, would be painful to the organization if they were

sluggish, non-responsive, or unavailable for a period of time. Users could stil l use their desktop for other

productive functions, such as Microsoft Office applications or researching on the internet.

Virtual Desktop Infrastructures, on the other hand, can represent a true disaster if they become sluggish

or non-responsive. The user is no longer impacted by only one or two applications but by the very

desktop itself. Imagine the majority of the workforce reduced to typing 10 or 20 words per minute or login

times in excess of 30 minutes. Any slowdown in the VDI ecosystem has a very “public” result. Storage

systems incur a tremendous performance penalty when performing disk drive recovery operations, and

these have a dramatically negative impact to the end-user experience. Even if data is separated into

“groups” or “sets,” centralized storage controllers are now responsible for managing recovery operations

in addition to ongoing operations. Storage companies would not generally consider this a “single point of

failure,” but users will.


Deploying and Expanding Desktops Pools

Over the course of the reference architecture testing, various user configurations were tested . At one

point in the testing, three desktop pools of 500 users each were expanded by 10 desktops each. This was

done while all of the desktops were powered on, but no workload was being applied (idle). Below is the

graph of the IOPS from the single ISE 740 system that was tested . Regular spikes in IOPS can be seen

to reach over 12,000 IOPS, and the entire operation lasted for roughly 10 minutes. Performing this activity

during the production period would have a significant impact to other functions that required storage

performance, unless the storage system had enough headroom to accommodate the additional load .

Traditional storage solutions that can accommodate this level o f activity are cost prohibitive and are often

undersized for this level of performance.

Figure 1 - Deployment Operations and High IOPS

The majority of the deployment time and performance requirements came from the Sysprep operations

for the Windows 7, 32-bit operating system. Cloning of the base images and creation of the View

Composer linked clones represented ~1/3 of the deployment time for the 30 desktops mentioned above.

In testing with large numbers of desktops (500), the time and pe rformance required for the Sysprep

functions (not cloning the base image) comprised the vast majority of the deploy operation time and

performance required.

Redefining “Steady-State” Operations

When sizing a VDI environment, many different operations must be planned for. Accommodating hosted

desktop users during “steady state” with a low-latency experience has to be satisfied during maintenance

operations. Boot storms and login/logout storms of relatively few numbers of users can push a storage

system designed only for “steady state” well past its breaking point. These operations are part of the

normal desktop access activity for users, and as such they should be included in any storage sizing

discussion for “normal” operations.

In testing with Login VSI, storage performance (IOPS) required during the user login phase was two times

the “steady-state” workload. Considerable thought should be given to user behavior patterns and how

many users will be concurrently initiating connections to the desktop environmen t. Login VSI is capable of

adjusting the rate at which users log in to the environment for the test and is an excellent method for

exploring the performance of the solution during various login activity levels. In the testing X-IO

performed, user login rates of 16/min, 25/min, and 33/min were tested. The single greatest impact to the


login times was the high compute (CPU and RAM) util ization of the UCS blade servers when the majority

of the users had connected to the solution.

VDI Planning Questions to Ask

Proper planning is essential to a successful VDI roll -out. Here is a non-exhaustive set of questions to help

guide your investigation into a VDI pilot program and your full production program.

What are the different kinds of users you will have to support (i.e., kiosks, developers, power users,

tellers, knowledge workers)?

What is the scope of each user type?

How many simultaneous desktops will be required?

What are the expected resource demands for each user (i.e., CPU, memory, disk space, network

traffic)?

What is the planned concurrency for your user pools and will their usage be offset from each other

(i.e., shifts, geographical support)?

What are the relative benefits for virtualizing desktop access for each user type?

What are the relative risks for each user type, if there are access issues?

What existing infrastructure can be used for the VDI implementation?

For each user type, would persistent or non-persistent desktops be more appropriate?

For each user type would linked clones, full clones, or dedicated virtual machines be more

appropriate?

What existing IT management and monitoring tools do you have in place?

Will your infrastructure support iSCSI? Fibre Channel? Is either preferable to you?

Will the pilot program be based on actual users or will it use validation software like Login VSI?

For the pilot program, what are your success criteria?

How much cost will there be in extending the warranty beyond what was included with the base

support period?

What metrics are important to you? For example:

o Total number of IOPS

o Total throughput

o Recompose wall -clock duration

o Maximum latency as seen by end user

o Virtual machine boot time

o Login / logout times

How will the transition from pilot program to full production implementation be done?


Solution Overview

This X-Pod reference architecture white paper describes a compact configuration to deliver a high -

performance VDI environment that supports up to 1500 virtual desktops. In the following sections, Cisco

UCS, Cisco Nexus, Cisco MDS, VMware vSphere, VMware Horizon View, and the ISE hybrid storage

array are described.

Components

The following components were chosen for this X-Pod reference architecture.

Cisco Unified Computing Systems (UCS)

The underlying premise of a VDI solution is to run user desktops on powerful datacenter servers rather

than on distributed physical machines. Cisco has focused on the characteristics needed to support this

functionality in datacenter servers and has developed the following innovations:

Extended memory

Virtualization optimization, with Cisco VN-Link technology

Unified I/O access and unified fabric

Unified, centralized management

Service profiles

The bottom line is Cisco has developed and refined the Unified Computing System to specifically meet

the Enterprise VDI requirements. Simplified architecture and management geared toward datacenter

fulfi l lment of virtual desktops leads to reduced total cost of ownership (TCO) by lowering acquisition costs,

lowering operating costs, and lowering ongoing operational costs.

The UCS unites compute, network, storage access, and virtualization into a cohesive system. The system

is integrated on a low-latency, 10-Gigabit ethernet (10GbE) unified network fabric with enterprise -class,

x86-architecture servers. It is an integrated, multi-chassis platform in which all resources participate in a

unified management domain. The Cisco UCS accelerates the delivery of new services simply, reliably,

and securely through end-to end provisioning and migration support for both virtualized and no n-

virtualized systems.

For more on UCS:

http://www.cisco.com/c/dam/en/us/solutions/collateral/data -center-virtualization/unified-

computing/at_a_glance_c45-523181.pdf

Cisco Nexus

The Cisco Nexus 5548P is a one-rack-unit (1U), 1 GbE, 10 GbE, and FCoE access-layer switch built to

provide 960 Gbps of throughput with very low latency. It has 32 fixed, 1 GbE, or 10 GbE p orts that accept

modules and cables meeting the Small Form-Factor Pluggable Plus (SFP+) form factor. One expansion

module slot can be configured to support up to 16 additional 1 GbE and 10 GbE ports or eight Fibre

Channel ports plus eight 1 GbE and 10 GbE ports. The switch has a single serial console port and a

single out-of-band 10/100/1000-Mbps Ethernet management port.

http://www.cisco.com/c/dam/en/us/solutions/collateral/data-center-virtualization/unified-computing/at_a_glance_c45-523181.pdf

http://www.cisco.com/c/dam/en/us/solutions/collateral/data-center-virtualization/unified-computing/at_a_glance_c45-523181.pdf


Cisco MDS

Cisco MDS 9148 Multi layer Fabric Switch is a high-performance Fibre Channel switch platform. It

provides low power consumption and high density with up to 48 line-rate 8 Gbps ports in one rack unit

(1U).

VMware Horizon View

Horizon View is used to deliver virtual desktops as a service in a broad range of enterprise use cases,

enabling the best user experience for maximum productivity. IT administrators can easily provision and

customize the environment to comply with corporate policy and end -user needs. Desktop virtualization

with Horizon View enables organizations to do more with less and adopt a user-centric, flexible approach

to computing. By decoupling applications, data, and the operating system from the endpoint —and by

moving these components into the datacenter, where they can be centrally managed in your cloud —

desktop and application virtualization offers IT a more streamlin ed, secure way to manage users and

provides agile, on-demand desktop services.

X-IO Technologies Intelligent Storage Element (ISE)

Consolidation and business intell igence are key themes in today’s IT. Consolidation brings with it

challenges in server multi-tenancy and hosted desktops while database management systems become

the keys to a successful business. In both cases, fast and reliable solutions lead to a more productive and

profitable enterprise. The ISE 700 series hybrid storage system keeps pace wi th the performance

demands of today’s IT without the high cost it takes traditional storage systems to keep up. The ISE 700

series provides an ideal balance of price, performance, capacity, and reliability by combining SSD and

HDD into a single hybrid pool of capacity to provide SSD performance at HDD pricing. ISE outperforms

systems that are up to ten times more expensive and provides an outstanding TCO by reducing operating

costs associated with management, power, cooling, and datacenter footprint.

ISE Manager Suite

Enterprise storage is not only facing a challenging future it’s facing a challenging present. Today’s

datacenters are increasingly heterogeneous and multifaceted. Virtualization technologies, diverse storage

platforms, and cloud services create obstacles for traditional storage systems and storage management.

How can you as a storage administrator be expected to efficiently and effectively manage storage in such

a complex environment? The answer lies in your management tools, which must have dee p integration

with virtualization technologies and host operating systems while being precise, streamlined, and user -

friendly.

Ideal for the challenging storage scenarios of modern enterprises, ISE Manager 4.0 is the solution for

today and tomorrow. It is an intuitive, flexible interface that provides simplified end -to-end storage

management for multiple physical, virtual, and cloud environments from a single interface. It lets you

simplify, centralize, and automate storage administration with software t ailored to modern datacenters.


Figure 2 - ISE Manager Suite

Login VSI

Login Virtual Session Indexer (Login VSI) is the industry standard load

testing tool for virtualized desktop environments. Login VSI can be used to

test the performance and scalability of VMware Horizon View, Citrix

XenDesktop and XenApp, Microsoft Remote Desktop Services (Terminal

Services), or any other Windows-based virtual desktop solution. Login VSI

may be used to compare and validate the performance of di fferent software

and hardware solutions in an environment. Login VSI provides a method to

measure the maximum capacity of an infrastructure. Simulated users work

with the same applications as an average employee , such as Word, Excel,

Outlook, and Internet Explorer.

For more information, download a trial at www.loginvsi.com

http://www.loginvsi.com/


Solution Architecture

This section highlights the hardware and software configurations used to assemble this reference

architecture for 500, 1000 and 1500 virtual desktops delivered with VMware Horizon View 5.3 on vSphere

5.5 U1.

This environment was built on top of two Cisco UCS B-Series chassis, Cisco networking components,

and X-IO 700 Series hybrid storage arrays.

Figure 2 shows the logical diagram of the solution architecture for 500, 1000, and 1500 virtual desktops.

The same infrastructure was used for all three tests.

Figure 3 - Logical Diagram for 500, 1000, and 1500 Desktop Reference Architecture


Hardware Components

The following hardware components were leveraged to support the Login VSI test of 500, 1000, and 1500

VDI desktop loads.

Hardware Quantity Configuration

Serv ers

Cisco UCS 5100 B-Series Chassis 1 1 500 Desktop Cluster

2208XP Fabric I/O Extenders 2

Cisco UCS B200 M3 1 Two Intel Xeon E5-2680 2.7-GHz CPU (16 cores total)

128 GB RAM

Infrastructure Blade


128 GB RAM

vSphere desktop cluster

VIC 1280 8

Cisco UCS 5100 B-Series Chassis 2 1 1000 Desktop Cluster



256 GB RAM

vSphere desktop cluster

VIC 1280 8

Cisco UCS 5100 B-Series Chassis 3 1 Login VSI Infrastructure


Cisco UCS B440 1 Two Intel Xeon E7-4870 2.4-GHz CPU (24 cores total)

256 GB RAM

Login VSI Server

UCS-VIC-M82-8P 8

Networking

Cisco Nexus 5548 2

Cisco MDS 9148 2 8 GB/s Fibre Channel Switch, 2 ports per ISE 700

Cisco UCS 6248 Fabric Interconnect 2

Storage

X-IO ISE 710 Hybrid Storage Array 1 8Gb/s Fibre Channel – for BfS Array

X-IO ISE 730 Hybrid Storage Array 1 8Gb/s Fibre Channel – for Login VSI Share

X-IO ISE 740 Hybrid Storage Array 1 8Gb/s Fibre Channel – for all Horizon View desktop

pools


Software Components

See the table below for software details.

Software Version

v Sphere

ESXi 5.5 update 1

vCenter Server

Operating System

Microsoft .NET

Microsoft SQL Server

5.5 update 1

Windows Server 2008 R2 64-bit Standard Ed.

3.5 SP1

2008 R2

VMware Horizon View

View Connection Server

Operating System

5.3.1


View Composer (installed on vCenter Server)

Operating System

5.3.1


Microsoft Software Platforms

Active Directory, DNS, DHCP Windows Server 2012

Login VSI, VSIshare Serv er

Operating System Windows Server 2008 R2 64-bit Standard Ed.

Microsoft .NET 3.5

Login VSI 4.0

Virtual Desktops: Target Desktop

Operating System Windows 7 32-bit

Microsoft Office 2010

Adobe Reader v. 11

Java SE 7 U13

DoroPDF

VMware View Agent 5.3.1

Virtual Desktop: Launch Desktop

OS Windows 7 32 bit

Cisco Unified Compute System (UCS)

The Cisco UCS configuration was connected to X-IO ISE 700 storage arrays through dual, redundant

paths to the MDS 9148 switches, then connected to the Cisco 6248UP fabric interconnect with dual,

redundant, 10 Gbps connections. This architecture provides for a highly available and high -performance

architecture.

Each Cisco UCS chassis was connected to each fabric interconnect with four 10 -Gbps network

connections.


The dual fabric interconnect pairs have primary and subordinate rol es in this configuration. For more

information about optimizing and configuring the Cisco UCS server service profiles for VDI, please refer to

the following link:

http://www.cisco.com/go/unifiedcomputing

VMware vSphere 5

For this test configuration, the VMware vSphere 5.5 Update 1, ESXi hypervisor was deployed. All of the

hosts were set up to boot from SAN (optional) using the X-IO ISE 710 hybrid storage array.

Clusters

The environment is organized into three main components: the VDI clusters, management cluster, and

Login VSI Launcher cluster. Two VDI clusters encompass a total of 15 UCS blades and are responsible

for supporting all target virtual desktops. The first VDI cluster of 7 nodes run s 500 VDI target desktops.

The second VDI cluster of 8 nodes runs 1000 target VDI desktops. 1 UCS blade (in its own cluster) is

used to run all infrastructure functionality, including a Domain Controller, vCenter, VASA provider,

vCenter Operations Manager, and Horizon View servers. The last cluster, the Login VSI Launcher cluster,

is a UCS blade that runs 80 Login VSI Launcher desktops.

VDI Clusters

The two clusters under test in this reference architecture are the VDI clusters. They consist of 15 hosts,

as described in the “Hardware Components” section above. These work together to support the test loads

of 500, 1000, and 1500 virtual desktop machines.

Figure 4 - VDI Cluster for 500 Desktops

http://www.cisco.com/go/unifiedcomputing


Figure 5 - VDI Cluster for 1000 Desktops

Infrastructure

The Infrastructure UCS blade houses all virtual machines to support the vSphere environment, the

Horizon View environment, and the Login VSI testing environment.

Figure 6 - Infrastructure VM for Reference Architecture Validation


VMware Horizon View 5 Environment Architecture

The VDI environment in this solution is created and managed in VMware Horizon View v5.3.1. To support

this, the vSphere environment runs in a singl e datacenter with three clusters and a single vCenter

instance. All hosts are running ESXi 5.5 U1.

VMware View 5.3.1 was used to construct and manage the desktop virtual ma chines. This test used a

floating pool of non-persistent, l inked clone desktop virtual machines. The details of the specific VMware

View pool definition are included in the Appendix of this white paper.

In addition to the linked clone method of deploying desktop virtual machines, VMware View 5.3.1 uses

VMware VSA technology. This technology allows a small amount of VMware ESXi host RAM to be used

as a content-based read cache for the selected desktops’ read I/O operations. VMware VSA was

configured at 2 GB for each VMware ESXi host and for each VMware View pool used for this test.

View Pools

The virtual machines in the 500 desktop VDI cluster were stored on four datastores, which are in turn stored

on four ISE LUNs. Each LUN is 1 TB in total capacity, configured with RAID-1 protection and housed on a

single ISE 740 hybrid storage array, as shown in the following ISE Manager and vSphere Client figures.

Figure 7 - Datastores for 500 Desktop View Pools (vSphere Client)


Figure 8 - LUNs for 500 Desktop View Pools (ISE Manager)

The 1000 desktop VDI cluster is configured in the same manner. Below is a screen shot of the datastore s

as they are configured.

Figure 9 - Datastores for 1000 Desktop View Pools (vSphere Client)


Multiple desktop pools were configured in VMware Horizon View to accomplish the tests. The first 500

desktop test used 5 pools, each with 100 desktops, as shown in the image below.

Figure 10 - Pools for 500 desktops

The 1000 desktop test was done with 2 pools of 500. The 1500 desktop test was done with 3 pools of

500. Below is a screen shot of the three desktop pools of 500, used in the 1500 desktop test.

Figure 11 - Pools for 1500 desktops

Target VMs

Base Image

OS Windows 7 32bit, Enterprise

VM Hardware Version 8

v CPU 1

Memory 1.5 GB

HD 16 GB

The target desktop virtual machines are created from a base image. This image was created as a stock

Windows 7 32 bit Enterprise operating system. Windows updates were applied to bring it to the current

levels. Several applications were then installed, including Microsoft Office, Adobe Acrobat Reader, and

FreeMind. The view agent is installed on the gold image, and a snapshot is created.


VMware vCenter Operations Manager

vCenter Operations Manager (vCOPS) is a monitoring, trending, and alerting tool . It gathers metrics on all

major components of the vSphere environment and automatically generates alerts if any values g o

outside of either manually or automatically set thresholds. Because vCenter Operations is extensible, it

can learn to monitor application and product specific characteristics.

This reference architecture uses two extensions to vCenter Operations:

vCenter Operations Manager for View

X-IO ISE Management Pack for VMware vCenter Operations

vCenter Operations Manager for View

The vCenter Operations Manager for View extension gathers information on the running Horizon View

environment. It automatically sets thresholds for View-related metrics and also adds many dashboards to

the vCenter Operations instance.

X-IO ISE Management Pack for VMware vCenter Operations

X-IO technologies has developed a vCenter Operations adapter extension that allows ISE storage units to

participate as a full -fledged member of the vSphere ecosystem. All major performance and configuration

metrics are captured and custom dashboards are added.

Figure 12 - vCenter Operations with ISE Management Pack


X-IO ISE 740 Hybrid Storage Array

The ISE 740 hybrid storage array has 28.8 TB of usable capacity configured from the highest-quality,

mission-critical 10K RPM SAS drives and enterprise-grade, MLC SSD into a single pool of flash-enabled

storage. The ISE 740 is fully redundant with active-active controllers, each including four 8 Gb Fibre

Channel ports. The ISE 700 Series includes patented Continuous Adaptive Data Placement (CADP)

software, which analyzes the behavior of host I/O and automatical ly places hotspot data onto SSD only if

measurable performance gains will be achieved. CADP runs continuously and makes data movement

decisions every 5 seconds.

In each of the 500, 1000, and 1500 user tests the ISE 740 delivered low-latency read and write

transactions for the entire duration of the tests and project.

Figure 13 - The ISE 740 Hybrid Storage Array


Performance Analysis of Tested configurations

Test Methodology

While storage vendors have for years util ized synthetic benchmark tools to simulate performance loads

(Iometer, SQLIO, fio, iozone), nothing can provide more insight into performance requirements than a

testing tool that performs actual end-user usage. Testing in this “systems view” methodology allows for

many different facets of the solution to be evaluated, as different virtual desktop operations have

drastically different requirements from storage. Simply using a load generator to show the performance

possible from a storage array and somehow relating it to desktop virtualization workloads completely

ignores the challenges that are unique to this solution design.

Login VSI was used as the load generation tool, as this is capable of mimi cking end-user functions, such

as working with Microsoft Office applications, running Java, browsing web pages, and other common user

functions. If the console is left open in one of the target desktops, this activity can be watched as the test

progresses. Login VSI provides a valuable framework to gather much more information than just the main

workload run, as will be detailed in the sections below. Other virtual desktop management operations

were also performed as part of the setup and environment mainte nance throughout the testing period.

Performing these actions proved invaluable to learning about the different workloads involved in the

solution.

Testing to determine the scale of the ISE 740 storage array was one of the goals in the testing, and Login

VSI test runs were performed with 500, 1000, and 1500 users. The “medium” workload setting was used

for this testing series, as per Login VSI this can be considered an avera ge workload for a virtual desktop

user. Login VSI measures the end-user desktop experience and produces a metric that is a measure of

the amount of desktops that a given solution could support with acceptable performance (VSImax). When

VSImax is reached, that is the estimated number of desktops the solution can be expected to support. In

all testing performed (500, 1000, and 1500 users), the Cisco UCS CPU util ization was the main limiting

factor to achieving higher numbers of desktops. The ISE 740 was able to accommodate all of the tested

user levels with no signs of a performance limit being approached.

Workload Analysis

Login VSI 500, 1000, and 1500 user Stead-State Workload

All users in this reference configuration were logged in and simulated by Login VS I. The workload chosen

for each of the remote users in all tests was “medium.”

Login VSI produces a metric called VSImax. This is a measure of the number of concurrent virtual

desktops that a given solution can support with “acceptable” desktop performance . Test iterations are

performed, and the goal is to closely match or exceed the number of desktops that are planned to be

concurrently run in production with the VSImax score.

Below are the results from the 3 test iterations (500, 1000, and 1500 desktops). A clear, l inear increase in

the VSImax score can be seen as the number of users was increased, indicating that the VDI solution

was able to accommodate the workload with no signs of encountering a performance bottleneck until 97%

or greater concurrency was achieved.


In the graphs above, VSImax is encountered at 492, 998, and 1466 sessions for the 500, 1000, and 1500

user tests respectively. This is due to the high resource util ization of the servers in this configuration. See

Figures 12 ad 13 for vCenter Operations Manager views of one of the server’s CPU and memory

resources during each of the 500 and 1000 user tests.

Figure 14 - VSImax for 500, 1000, and 1500 Users


Figure 15 - Server Resources During 500 User Test

Figure 16 - Server Resources During 1000 User Test

One of the things that makes the virtual desktop workload so challenging for storage solutions is the high

amount of write operations that are required, especially considering the write penalties involved with RAID

operations. During the steady state testing, write operations to storage were observed to be 80% of the

total IOPS.


Below are graphs of the Total ISE System IO (Write and Read) in the 3x test runs (500, 1000, and 1500).

Write IO can be clearly seen dominating the workload mix. Total IOPS values on the 1,500 user test were

observed to regularly occur above 10,000 IOPS at the height of the login phase of the run.

It was observed that write IOPS were higher in the login phase of the test run. The steady state Login VSI

tests required the least amount of performance (IOPS) from the ISE 740 hybrid storage array.

Figure 17 - Login Phase and Steady State For 500, 1000, And 1500 Users

Figure 18 - Write Latency for 500, 1000, and 1500 User Tests


Figure 17 shows that the ISE 740 array performed all of the write operations under 10ms, with 99% of all

operations well under 5ms during the 1500 user tests. There are 3x periodic increases in write latency at

the end of the 1000 user test due to Storage vMotion operations, which were included in the 1000 series

graph to show the effect of this operation during testing. Values of bel ow 1ms are reported as 0ms, and

as such the 500x desktop series can be thought of as having no observable latency over 1ms for the

testing period.

Read latency is also an important measure of system performance, and increases in read latency were

observed as the system load increased (as would be expected). The highest values were observed in the

1500 desktop series, with 95% of the average values below 10ms. Th e Storage vMotion operations

(1000) had the most impact to the read latency values; however, this did not appear to be enough to

impact the VSImax score significantly. The vast majority of the read latency value for the 500 desktop test

were below 1ms (0 values).

Figure 19 - Read Latency for 500, 1000, and 1500 User Tests

Read latency is the value that will react first when increasing load on the storage system. However, the

amount of read IOPS comprises a small percentage of the overall workload.

The ISE 740 hybrid storage array demonstrated that it was able to satisfy the Login VSI workloads up to

the point of saturation (100% util ization) for the Cisco UCS CPU resources of the 15 Blade servers. The

Login phase of the test scenario generated up to twice as many IOPS than the main Login VSI “medium”

workload. If large volumes of users are logging in/out of the environment concurrently, storage

performance will play an important role.

Virtual Desktop Deploy Operations

Deploy operations are something that every environment must go through. Whether performing the initial

creation of the desktops or performing a recompose operation, this process replicates copies of the “gold

image” to the various datastores that will contain the desktops and prepares the operating system for use.


This operation had the least impact to Cisco UCS server resources and was mainly limited by the rate at

which desktops were deployed by Horizon View. CPU util ization rates stil l reached 40%, and memory

util ization stabilized at 80% by the end of the process. Consideration should be given to the CP U and

memory increase in the event that this process occurs during “production” hours.

The deploy operation performance requirements are biased towards storage write IOPS, at just over 60%

of the workload. Average values for total storage IOPS demand were seen to regularly approach 20,000

IOPS, with high values approaching 25,000 IOPS. This process operates over all of the VM “active” data

set size and generates I/O across all of the new desktop capacity.

Figure 20 - ISE 740, Total Read and Write IOPS During Deploy Operation

Response time is also an important measure to examine when performing system “stress testing.” The

deploy process is one example of what a virtualization administrator may conduct to proof out storage

systems being proposed for VDI deployments. The ISE 740 shows excellent read and write response for

this workload, with the majority of the write and read latency values below 2ms and 4ms, respectively.

The reduction in read and write latency seen at the beginning of the test run is due to the ISE

management of data to SSD in real time. This is Continuous Adaptive Data Placement (CADP) in action,

as it learns the workload and optimizes for best performance —automatically.

Figure 21 - Read and Write Latency During Deploy Operation

Smaller pool sizes would result in less load being placed on the Cisco UCS CPU and memory resources

and would have a significant reduction in the amount of storage IOPS. In relation to the main Login VSI

workload, the deploy operation required greater than 200% more storage performance than the “medium”


workload. Reduced desktop pools sizes should be considered for smaller environments that do not

require deploying or recomposing large numbers of desktops (>500). Over the course of the testing, the

desktop creation process was run several times and provided invaluable information on the impact of this

operation. The ISE storage array was able to satisfy this workload with excellent response times.

Larger numbers of desktops per pool will result in large numbers of deploy operations happening with

maintenance operations. This may be completely acceptable if this entire configuration is viewed as a

single “POD,” and there are multiple “PODs” in the solution. Smaller en vironments, where this

configuration would represent the entire solution, should consider using smaller desktop pool sizes to

better control the impact of these operations on production users.

Virtual Desktop Boot Storm

The virtual machine boot process was the most taxing on the CPU util ization. The figure below shows the

processor and memory util ization of a single blade server during this process. CPU util ization reaches

saturation (100%) as the different pools of desktops are booted. Limiting the desktop pool sizes should be

considered, as this can limit the impact and duration of the event if an entire desktop pool needs to be

booted or rebooted.

The boot process varied from 100% write to 100% read over the duration of the test. Initially, there is a

large write workload, which then changes to mostly read, and then another write component resurfaces

toward the end of each group of desktops booted. Write IOPS during this period were observed to reach

above 30,000 IOPS and read activity past 40,000 IOPS. This increase in performance is due to the

adapting caching of the ISE controller hardware and the automatic real -time management of data

between SSD and HDD (CADP).

Figure 22 - Total Read and Write IOPS During Boot Storm

In total, the ISE 740 hybrid storage array regularly reached levels over 40,000 IOPS during the boot

process and transferred data at over 600 MB/sec.


Figure 23 - Total IOPS and MB/s for Boot Storm

Response times of the ISE 740 were well within what would be considered normal for database

operations, proving that the ISE was not approaching any limit in performance for this operation.

Figure 24 - Read and Write Latency During Boot Storm

Boot storms are traditionally extremely difficult for storage systems to keep up with. The broad range of

read vs. write requirements, while requiring high-performance IOPS, are usually where most storage

systems have significant issues. In thi s test, the main limiting factor was the Cisco UCS CPU resources

as all servers were pushed to 100% CPU util ization. When planning for numbers of consecutive desktops

that can be safely started at the same time, careful attention should be paid to the proc essor util ization of

the ESXi servers after high-performance storage is implemented (such as the ISE 740 hybrid storage

array).


Conclusion

When it comes to deploying virtualized desktop deployments, it’s clear that there is a dangerous

combination of misleading marketing statistics and many implementation pitfalls out there . However the

purpose of the X-Pod for VDI solution is to provide enough insight and proof points into the performance

and sizing of a virtual desktop infrastructure with Cisco UCS B-Series Servers, based on an X-IO ISE 700

Series hybrid storage arrays, This therefore provides an appropriate converged infrastructure design to

competently design a suitable architecture for a high-performance hosted desktop end-user experience.

While i t provides a simple, easy to deploy model for the user counts suggested, it should be noted that

these are high-end assumed guidelines and X-IO and its VDI partners will be happy to help provide a

customized X-Pod solution to meet the VDI specifications needed.

Contact X-IO technologies

Website: http://www.xiostorage.com/ Email: [email protected]

Get in touch with us:

http://xiostorage.com/contact/

or

Visit our website and chat with us to get more

information.

United States »

866.472.6764

International »

+1.719.388.5500

9950 Federal Drive, Suite 100 | Colorado Springs, CO 80921 | U.S. >> 1.866.472.6764 | International. >> +1.719.388.5500 | www.x-io.com

X-IO, X-IO Technologies, ISE and CADP are trademarks of Xiotech Corporation. Product names mentioned herein may be trademarks and/or

registered trademarks of their respective companies. © Xiotech Corporation. All rights reserved. RA-0003-20140825

http://www.xiostorage.com/

mailto:[email protected]

http://xiostorage.com/contact/


Appendix

Appendix A: Detailed Analysis of vSphere Performance Graphs, Login VSI

500 User Run

In performing this testing, CPU and RAM limitations of the Cisco UCS

equipment was the main limiting factor in almost all operating

“modes.” To the right is an image saved from the CPU Performance

tab of the vSphere Windows Client (SVR-108). In this case, booting

500x users is being performed as part of the “test reset” process,

before starting a Login VSI workload. A spike to 100% util ization can

clearly be seen as the desktops are powered on, and all of the other

servers (15x) exhibit this same behavior.

As with any Virtual Desktop deployment, memory management is

an important role as well when sizing VMs and examining

performance limits of a solution. Performing a boot operation

consumed virtually 100% of the server’s RAM resources (big drop in

the graph to the left). Subsequent optimizations were made to the

desktop OS image that reduced the memory requirements to

roughly 83% of the server’s capacity.

The Login Storm portion of the testing showed the same

response from the blade servers’ CPU util ization. To the right

is the VMware CPU performance graphs that include the

above mentioned boot storm and the 30-minute login phase of

a test run (16.67 logon/sec). Processor resources are clearly

stressed to 100% well before the end of the login phase . The

constraint to blade server CPU resources over the course of

this testing was the single greatest l imiting resource in every

case, not storage performance. This constraint was the same

across all 15x servers used in the testing series and through

the Login VSI run phase.


Appendix B: EXAMPLE Login VSI Target Desktop Pool Configuration

pool 2

pool_id Floating_Pool_4_LoginVSI

description

displayName Floating_Pool_4_LoginVSI

enabled FALSE

folderId /

deliveryModel Provisioned

multiSessionAllowed FALSE

userResetAllowed FALSE

assignOnFirstLogon TRUE

desktopSource SVI

powerPolicy RemainOn

vc_id f4e1017d-1986-4124- 95d9-04f80ef020c f

vcServerName 10.64.64.20

parentVMPath /XIOUCSVMW/vm/aTarget_Base_3.1_Hig hPerf

parentVMSnapshotPath /First Snap

parentVMSnapshotM OID snapshot-33101

refreshPolicy type=Never;

persistentDiskSpecs [DiskSize=4096;DiskUsag e=Sys temDisposabl e;UseSparse=tr ue;MountPoint=*;]

datastoreSpecs

Pool0;[Aggressive,OS,data]/XIOUC SVM W/host/XIOUCSVM W-VDI Cluster High Perf/ISEC-HighP-




usevSphereM ode TRUE

composer_ad_i d d907f262-b37f-47e9-8f51-0a1710b58150

composerDomain XIOUCSVMW.LAB

composerDomainUser Administrator

postSyncScript

logoffScript

organizationalUnit CN=Computers

minprovisioneddesktops 0

networkLabelSpecs disabled

provisionEnabled FALSE

provisionSuspendOnError TRUE

postProvisionState READY

startClone TRUE

calculatedValues FALSE

deletePolicy Default

headroomCount 500

maximumC ount 500

minimumCount 500

datastorePaths

/XIOUCSVMW/hos t/XIOUC SVM W- VDI Cluster High Perf/ISEC-HighP-

Pool3;/XIOUCSVM W/host/XIOUC SVM W-VD I Cluster High Perf/ISEC-HighP-


Pool1;/XIOUCSVM W/host/XIOUC SVM W-VD I Cluster High Perf/ISEC-HighP-Pool 0

datastoreDisplayPaths

/XIOUCSVMW/hos t/XIOUC SVM W- VDI Cluster High Perf/ISEC-HighP-



Pool1;/XIOUCSVM W/host/XIOUC SVM W-VD I Cluster High Perf/ISEC-HighP-Pool 0

customizationSpec LoginVSI Target Spec 3.x - GOOD

resourcePoolPath /XIOUCSVMW/hos t/XIOUC SVM W- VDI Cluster High Perf/Resources

resourcePoolDisplayPath /XIOUCSVMW/hos t/XIOUC SVM W- VDI Cluster High Perf/Resources

vmFolderPath /XIOUCSVMW/vm/Login VSI/Floating_Pool_4_LoginVSI

vmFolderDisplayPath /XIOUCSVMW/vm/Login VSI/Floating_Pool_4_LoginVSI


namePrefix atargetE{n:fixed=4}

persistence NonPersistent

autoLogoffTime Never

poolType SviNonPersistent

markedForDelete 0

protocol PCOIP

allowProtocolOverride FALSE

flashQualityLevel NO_CONTROL

flashThrottlingLevel DISABLED

X-Pod for VDI Reference Architecture Enabled by Cisco UCS, VMware Horizon View, and ISE 740 Hybrid...

Technology

Transcript of X-Pod for VDI Reference Architecture Enabled by Cisco UCS, VMware Horizon View, and ISE 740 Hybrid...