Citrix and Intel help customers succeed with virtualization

Whether you’ve already implemented a virtualization solution or are considering this technology, there are new ways to optimize the performance of the virtualized environment and achieve greater benefits. Citrix Systems, Inc., and Intel have joined forces to provide solutions boosting reliability, availability and performance; enabling integration of 64-bit platforms; and streamlining system administration. Citrix® XenServer™ virtual server software running on Intel® Xeon® 5300 – 7400 Series processors, together with Intel Virtualization Technology (Intel VT) for optimizing virtual machine monitors (VMMs) like XenServer, can help your current or planned virtualization solution perform at its peak.

Citrix and Intel

2

The drive to virtualize

Virtualization technologies are enjoying rapid adoption because of their compelling benefits. The ability to run multiple operating platforms simultaneously in protected environments (virtual machines) on a single piece of hardware offers a multi-faceted solution to today’s business and IT challenges. Virtualization allows you to:

Consolidate servers and optimize their utilization to cut datacenter costs and reduce power •consumption

Rapidly reallocate resources within the datacenter or among several datacenters for improved •agility, business continuity and scalability

Boost reliability by providing backup and failover within the system•

Streamline system administration•

The challenge of legacy processors

Ideally, a virtualization solution should ensure isolation and high performance for each virtual machine while maintaining high overall server performance. Like any new technology, however, virtualization presents certain challenges. One of these involves the role of VMMs, which handle system virtualization. Operating systems are designed to have direct access to server platform resources without sharing. To accommodate a virtualized environment with multiple operating systems, the VMM must emulate the server hardware environment to the extent that the hosted operating platform on each virtual machine cannot tell it doesn’t own the entire hardware. The VMM must also be able to handle unusual situations such as software errors and hardware malfunctions. Legacy processor architectures are a roadblock to VMMs because they were designed to run a single instance of the operating system—not multiple instances.

Intel VT technology enhances Citrix XenServer

Citrix XenServer is a software-based, native 64-bit server virtualization solution that leverages the open source Xen® hypervisor. It is designed for efficient management of Windows® and Linux virtual machines. To help XenServer run more effectively, Intel offers VT technology, which is integrated into Intel Xeon processors. Intel VT provides robust hardware support for virtualization that facilitates deployment of XenServer and provides greater reliability and manageability of host operating systems.

Here’s how it works:

All modern processors and operating systems utilize the concept of privilege levels to define which actions can be performed by specific processes. Intel architecture provides four levels of privilege, called rings, numbered 0-3. The highest level, 0, is used by the operating system; and the lowest, 3, is used by applications. Only operating systems running in ring 0 have unrestricted access to the server hardware.

Open-source Xen HypervisorThe foundation of Citrix XenServer is the open source Xen hypervisor, a proven and fully supported engine for server virtualization. Xen is a unique, open-source virtualization technology invented by a team led by Ian Pratt at the University of Cambridge and developed cooperatively by the world’s best engineers at 20 of the most innovative vendors, including Intel, Citrix, IBM, Hewlett-Packard, Novell, Red Hat and Sun Microsystems.

Native SW (Para-virt) Intel VT-d

3.7 3.7

1.8

Intel® VT-d performance with 4 NICs

iPerf with Xen 3.2 and 64-bit Linux Kernel (2.6.18.8)

Thro

ughp

ut (G

bps)

3

For the VMM to work properly, it must run in ring 0 and create the illusion for the guest operating systems that each is running in ring 0. But since the VMM is itself running in ring 0, no guest OS can also run at this privilege level; instead, they typically run in ring 1. This forces the VMM to monitor the activities of each virtual machine to trap hardware accesses and system calls, execute them itself and emulate the results. Intel VT enables the hardware to take over these functions, reducing the computational burden on the VMM.

This is accomplished by creating two classes of rings, a higher 0P ring in which Citrix XenServer can run, and a non-root ring (0D) for the operating systems. This ensures the VMM has privileged control over platform resources, and supports handoffs between the VMM and guest OS to avoid complex, compute-intensive software transitions that can impact VMM performance.

Benefits of Intel technology with Citrix XenServer

Citrix XenServer is acknowledged as the best-performing and most secure virtualization software in the industry. XenServer is designed to fully leverage the benefits of Intel VT virtualization hardware-assist capabilities. And Intel Xeon processors provide the high performance and flexibility needed for demanding virtualization workloads. By leveraging Intel Xeon processors with VT technology to run Citrix XenServer, you can improve the performance and reliability of your virtual environment.

Near bare-metal performance to maximize server investment•

Greater reliability and scalability•

Reduced risk of software conflicts•

Support for 64-bit and 32-bit guest operating systems•

Stronger isolation of VMs, which prevents issues from one VM from affecting others•

Citrix and Intel: Working together to optimize virtualization

Citrix and Intel are providing a new generation of virtualization technologies that can help organizations like yours transform static, underutilized datacenters into dynamic, agile application delivery centers. Together, the companies are helping to drive standardization, provide higher-performing virtualization platforms, and enable easier adoption of 64-bit computing. They are making significant investments in new technology to help you succeed with virtualization.

Citrix virtualization solutions

The Citrix Delivery Center™ family is an application delivery infrastructure system that lets IT virtualize application resources, manage them centrally, accelerate their performance, and securely deliver to users anywhere. Through the Citrix Delivery Center portfolio, Citrix provides server, desktop and application virtualization solutions, all designed to transform the datacenter from a static, production-oriented facility to a dynamic, service-oriented delivery center.

Leading the way, Citrix XenServer, Platinum Edition enables IT organizations to deliver dynamic data centers. It couples a powerful platform managing virtualization as a flexible aggregated pool of compute and storage resources with rapid, cost-effective provisioning capabilities for both virtual and physical servers.

Intel Xeon processors

Intel Xeon 5300 – 7400 Series processors, based on the Intel® Core™ microarchitecture, offer scalable performance and best-in-class virtualization for server consolidation. You can experience up to 2-fold greater scalable performance, 2.5-fold greater virtualization performance, and 3-fold performance improvement per watt than the industry-leading Intel Xeon processor in the same power envelope. They enable you to be more productive and reduce datacenter space, power and administration/operation costs by consolidating your datacenter onto fewer servers.

About Citrix

Citrix Systems, Inc. (Nasdaq:CTXS) is the global leader and the most trusted name in application delivery infrastructure. More than 200,000 organizations worldwide rely on Citrix to deliver any application to users anywhere with the best performance, highest security and lowest cost. Citrix customers include 100 percent of the Fortune 100 companies and 99 percent of the Fortune Global 500, as well as hundreds of thousands of small businesses and prosumers. Citrix has approximately 6,200 channel and alliance partners in more than 100 countries. Annual revenue in 2007 was $1.4 billion.

About Intel

Intel, the world leader in silicon innovation, develops technologies, products and initiatives to continually advance how people work and live. Additional information about Intel is available at www.intel.com.

©2008 Citrix Systems, Inc. All rights reserved. Citrix®, Citrix Delivery Center™, Citrix Provisioning Server™, Xen®, XenApp™ and XenServer™ are trademarks or registered trademarks of Citrix Systems, Inc. and/or one or more of its subsidiaries, and may be registered in the United States Patent and Trademark Office and in other countries. Intel®, Centrino®, Intel vPro*, Pentium® and Xeon® are registered trademarks or trademarks of Intel Corporation in the U.S. and/or other countries. Microsoft® and Windows® are registered trademarks of Microsoft Corporation in the U.S. and/or other countries. All other trademarks and registered trademarks are property of their respective owners.

Citrix WorldwideWorldwide headquarters

Citrix Systems, Inc.851 West Cypress Creek RoadFort Lauderdale, FL 33309USAT +1 800 393 1888T +1 954 267 3000

Regional headquarters

AmericasCitrix Silicon Valley4988 Great America ParkwaySanta Clara, CA 95054USAT +1 408 790 8000

EuropeCitrix Systems International GmbHRheinweg 98200 SchaffhausenSwitzerlandT +41 52 635 7700

Asia PacificCitrix Systems Hong Kong Ltd.Suite 3201, 32nd FloorOne International Finance Centre1 Harbour View StreetCentralHong KongT +852 2100 5000

Citrix Online division5385 Hollister AvenueSanta Barbara, CA 93111USAT +1 805 690 6400

www.citrix.com

www.citrix.com