Cloud-Optimized Performance: Enhancing Desktop Virtualization Performance with Brocade 16 Gbps

(1)

DATA CENTER

Cloud-Optimized Performance:

Enhancing Desktop Virtualization

Performance with Brocade 16 Gbps

(2)

C

ONTENTS

Contents...2

Introduction...3

Cloud-Optimized Performance: VDI environment in a Private Cloud...3

Understanding the Storage IOPS in a VDI environment...4

Brocade 16 Gbps Fibre Channel and Large Scale VDI environments ...5

(3)

I

NTRODUCTION

As customers look to Fibre Channel (FC) storage area networks (SANs) for building private storage cloud services for their enterprise data centers, some of the key attributes are:

• Consolidated and highly virtualized pools of compute, storage and network resources • Secure and efficient use of inter-fabric connectivity

• Lower capital and operational costs, higher asset utilization

• On-demand and efficient provisioning of application resources through automated management

Brocade has developed solutions to address these key attributes leveraging its seventh-generation “Condor3” ASIC features in the 16 Gbps platform, Fabric Operating System (FOS) v7.0, Brocade Network Advisor, Brocade HBA and CNA technology, and are working with transceiver vendors to address these key requirements.

In order to enable customers to achieve these goals, Brocade is delivering key technologies (see Figure 1) that would allow customers to:

• Scale up/out based on business growth

• Secure data and optimize inter-data center bandwidth utilization

• Reduce CapEx and OpEx cost with build in diagnostics and SAN management tools • Optimize both bandwidth and IOPS while being energy efficient

Figure 1. Enabling Private Storage Clouds

Cloud-Optimized Performance: VDI environment in a Private Cloud

This is one of four technical briefs addressing Brocade solutions for helping customers in their transition to private storage clouds. In today’s virtual environments, the Storage Area Network (SAN) is being pushed to support

(4)

Understanding the Storage IOPS in a VDI environment

Many companies are moving towards a VDI environment, due to the benefits gained. Virtual desktop infrastructures simplify desktop management and reduce the typical issues faced when dealing with distributed desktops. With VDI, desktops are delivered quickly and reliably to any linked location. You control which devices are linked to a virtual machine (VM) controlling data management and reducing the potential loss of intellectual property (IP). This setup also has a significant effect on the cost of each desktop, sometimes reducing it by as much as 40%. You can also reduce the number of images you must manage, especially when working with volatile PC images, or those that are created as needed when users log into the system. Patches and updates are also easier to apply since you often only need to update one core image. VDI transforms the desktop lifecycle and reduces its number of components. Traditionally, you must procure, image, secure, deploy and then monitor, maintain, back up and retire your physical desktops. With VDI, you only need to generate the original image by creating a reference computer, use it as the core image for all systems, personalize it, monitor and update it.

VDI environments must be architected correctly to ensure an optimal end user experience. There are many considerations that must be reviewed but a major focus should be spent on the SAN side of the VDI environment. The SAN side hosts the actual client data which includes the golden image, the personalized environment of each VDI user and the VM data. Since the SAN hosts all the data, the number supported by the SAN environment must be determined. This number determines the amount of VDI users that can be supported.

To estimate the I/O capabilities of a basic SAN array, customers should perform as part of best practices, the following calculation (note that doesn't take into account anything unique or special about each vendor's solutions). The calculation is based on the number of drives (after raid and spares) that is multiplied by the approximate IOPS per device and then multiplied by the cache performance improvement factor (for read and write) - which varies based on load to somewhere between 20% and 70% (the more overloaded the array, the worse the cache factor). For example:

• A 16 SAS drive array with RAID 5 and one spare, it is 14 drives

• Each SAS 15K RPM is about 200 IOPS, so with 14 devices * 200 IOPS = 2,800 IOPS

• Adding Cache capabilities roughly optimized at 50%, would be 2,800 * 150% = 4,200 IOPS. Please note that if the array is using SSD, then the IOPS are roughly 10,000 or better. This is not

uncommon per device, and the latency is much lower because they don't have to seek a random position on the disk drive. Knowing the total IOPs provided by the array will determine the number of VDI users that the array can support correctly.

The number IOPS used by the VDI user falls into four categories: • Boot — 26 IOPS

• Login — 14 IOPS (Note for Windows 7 = 100 IOPS) • Work — user dependent

(5)

Using the following formulas, customers need to estimate the size of the array by IOPS:

Peak IOPS: Represents the peak IOPS expected based on the parameters provided. The following formula is used to calculate this value:

Peak IOPS = MAX((DesktopsInLoginState * Login IOPS) + (DesktopsInWorkloadState * Workload IOPS))

Note: DesktopsInLoginState is the number of desktops that are logging in and will move to the workload state

Steady-State IOPS: Represents the amount of IOPS necessary to execute the normal workload. The following formula is used to calculate this value:

Steady-State IOPS = Number of Desktops * Workload IOPS

Boot and Login Storms are a peak I/O moment that can dramatically affect performance. While boot storms can be addressed by phased-in power-ons before the workforce arrives, there is little that can be done to work around the I/O demands of a login storm, other than accelerating storage I/O performance.

To estimate the number of VDIs that the array can support during this boot storm without a performance hit, the following formula should be used:

Boot Storm Size = Total IOPS available from the array / 300

To estimate the number of simultaneous logins that the array can support during this login storm without a performance hit, the following formula should be used:

Login Storm Size = Total IOPS available from the array / 100

Note: As shown above, SSD and Hybrid arrays should be used in larger VDI environments as these arrays can support higher IOPs and provide lower latency.

Once the sizing for the array has been determined, the transport must be determined. The transport is the connectivity from the Hypervisor to the array. The typical connections are iSCSI, FCoE and FC.

Brocade 16 Gbps Fibre Channel and Large Scale VDI Environments

Large scale and private clouds VDI environments are usually 5000 or more VDI users with a high transaction rate (i.e.: Trading Floors) that require Fibre Channel SSD or hybrid arrays. This requirement is due to the heavy amount of IOPs generated by the VDI users and low latency provide by the SSD array. To support the high transaction

applications on SSD arrays where latency needs to be low and the throughput is maximized for a large number of IOPs, Brocade introduces 16 Gbps Fibre Channel Fabric Adapters and switches. The Brocade 16 Gbps platforms provide hyper-scale IO performance combined with proactive flow control to handle these new private cloud workloads. The Brocade 16 Gbps platforms provide:

• 500K+ IOPS per port, 16 Gbps Brocade 1860 Fabric Adapter • 700ns latency, 420M frames/sec per switch ASIC

(6)

Brocade 16 Gbps FC uses 64b/66b encoding, outlined in Table 1. Doubling the throughput of 8 Gbps to 1,600 MBps, it uses 64b/66b encoding to increase the efficiency of the link.

Speed Throughput (MBps) Line Rate (Gbps) Encoding 1 GFC 100 1.0625 8b/10b 2 GFC 200 2.125 8b/10b 4 GFC 400 4.25 8b/10b 8 GFC 800 8.5 8b/10b 10 GFC 1200 10.53 64b/66b 16 GFC 1600 14.025 64b/66b

The following is an example of the heavy usage seen in a 5000 VDI user high transaction rate environment, were the users are considered heavy:

Desktops In Login State

Login IOPs (assuming Windows 7 OS)

Desktops In

Workload State Workload IOPs

Number of Desktops

1250 100 3750 50 5000

Peak IOPS = 312,500 = 3750 desktops*50 IOPS/desktop + 1250 Logins*100 Login IOPS Steady-State IOPS = 250,000 = 5000 desktops*50 IOPS/desktop

S

UMMARY

(7)

Brocade, the B-wing symbol, BigIron, DCFM, DCX, Fabric OS, FastIron, IronView, NetIron, SAN Health, ServerIron, TurboIron,and Wingspan are registered trademarks, and Brocade Assurance, Brocade NET Health, Brocade One, Extraordinary Networks, MyBrocade, VCS, and VDX are trademarks of Brocade Communications Systems, Inc., in the United States and/or in other countries. Other brands, products, or service names mentioned are or may be trademarks or service marks of their respective owners.