& cplSiteName &

Virtual Machine Fabric Extender Performance

Light Reading
Series Column
Light Reading
1/29/2012
50%
50%

EXECUTIVE SUMMARY: The Cisco UCS’s Virtual Machine Fabric Extender (VM-FEX) offers consistently increased network performance operations compared to virtual distributed switch installations.


In a standard Local Area Network, various hosts, laptops and PCs typically connect to a Layer 2 switch that aggregates the physical stations before handing them off to a router. Communication between two hosts on the same LAN can be done directly without reaching the router. Similarly, a virtual switching instance passes traffic either to a VM sitting in the same hardware, or pushes it out the physical port. Virtual Switches (such as the Cisco Nexus 1000v or VMware’s vNetwork Distributed Switch) operations are done in software and Virtual Switches (such as the Cisco Nexus 1000v or VMware’s vNetwork Distributed Switch) operations are done in software and therefore take resources away from the virtual machines hosted on the blade. Reducing the amount of resources available to the VMs.

Cisco's Nexus 1000v has a rich set of capabilities such as VLAN aggregation, forwarding policies and security. Cisco, however, found that not all VM installations require these features, and in such cases it makes sense to save the resources taken by the virtual switch and appropriate them to the customer needs.

Cisco claimed that their Virtual Machine Fabric Extender (VM-FEX) in VMDirect mode replaces the switch and shows a significant increase in CPU performance for network intensive applications. VM-FEX, installed on VMWare ESX 5.0, enables all VM traffic to be automatically sent out on the UCS's Virtual Interface Card (VIC). This meant more traffic on the physical blade network interface, but reduced CPU usage, which is typically the VM bottleneck. To verify that the VM-FEX really frees up CPU resources, we ran a series of tests comparing a VM-FEX-enabled UCS blade to a Nexus 1000v virtual switch setup. Both UCS blade installations were identical in all aspects apart from the use of the VM-FEX in one and Nexus 1000v in the other.

We started comparing the performance between the two setups using Ixia’s virtual tools. We installed four Ixia IxNetwork VMs on each of the two UCS blades and sent 3,333 Mbit/s of traffic from each of the first three VMs, toward the fourth for 120 seconds using 1,500-byte frames. In the VM-FEX case we recorded 2.186 percent frame loss, while in the distributed switch environment we recorded 16.19 percent frame loss.

We expected loss in both cases, given the almost 10Gbit/s load we were transmitting in the virtual space. The load was required in order to really keep the CPU busy. We deduced from this initial test result that in the VM-FEX environment less resources were used, which is why the frame loss we recorded was smaller than the loss recorded in the virtual distributed switch setup.

For the next test setup we installed one IxLoad VM on each of the two blades. We configured both IxLoad VMs as HTTP clients that requested traffic from a Web server Cisco configured. The IxLoad emulated clients were configured to try and use as much bandwidth as possible by requesting 10 different objects from 10 URLs repeatedly. The VM-FEX setup reached 9.87 Gbit/s while the distributed switch reached 7.78 Gbit/s. The CPU usage was also significantly higher in the virtual distributed switch setup when compared to the VM-FEX setup.

Using the Ixia test tools we recorded the performance difference we expected. Cisco recommended that we perform a test that relies more heavily on the Storage Area Network (SAN). For this test, Cisco helped us to set up 10 VMs on each of the two setups, and install IOmeter on each virtual machine. IOmeter was configured to read blocks from an iSCSI-based SAN as fast as it possibly could. We manually started each of the twenty IOmeter instances, and after 10 minutes we manually stopped each of them. At the end, we looked at three statistics -- Input/Output Operations per Second, Data Rate, and Average Response Time -- all three averaged across the 10 VMs in each setup. The VM-FEX performance was indeed higher for all three metrics. The data is shown in the graph below:

We were still curious what the difference would be when someone is running a common task on a single VM. We wrote a script to use the open source program mplayer to encode a DVD image file that was stored in the SAN into mpeg (for private use of course). We wrote two versions of the script -- one performed an additional round of encoding. The results of this test run actually showed that the act of fetching blocks off the network-attached DVD were not too resource intensive as the VM-FEX setup required only marginally less time to perform the encoding than the virtual distributed switch setup.

Perhaps the most interesting metric was not the performance, but rather the CPU utilization. How much of the CPU was used for the operation, and how much was left over for other operations and other users? As shown below, the VM-FEX setup used far less of CPU resources in all cases. This was expected, since the CPU was skipping an entire layer of virtual switching, and this was, after all, exactly what Cisco wanted to demonstrate.


Next Page: Virtual Security Gateway
Previous Page: Unified Fabric (UF) – UCS Manager


Back to the Cisco Test Main Page

(0)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
Educational Resources
sponsor supplied content
Educational Resources Archive
Light Readingís Upskill U is a FREE, interactive, online educational resource that delivers must-have education on themes that relate to the overall business transformation taking place in the communications industry.
LIVE NOW!
Friday, December 2, 1:00PM EST
The SDN Approach to IP & Optical Integration
Sterling Perrin, Senior Analyst, Heavy Reading
UPCOMING COURSE SCHEDULE
Friday, December 2, 1:00PM EST
The SDN Approach to IP & Optical Integration
Sterling Perrin, Senior Analyst, Heavy Reading
in association with:
From The Founder
Light Reading today starts a new voyage as part of a larger Enterprise.
Flash Poll
Live Streaming Video
Charting the CSP's Future
Six different communications service providers join to debate their visions of the future CSP, following a landmark presentation from AT&T on its massive virtualization efforts and a look back on where the telecom industry has been and where it's going from two industry veterans.
Women in Comms Introduction Videos
Korn Ferry Consultant: How to Find, Cultivate & Be the Best Talent

11|30|16   |   4:10   |   (1) comment


Erin Callaghan, a managing consultant for Korn Ferry Futurestep, shares strategies for companies to improve how they recruit and for women to ensure they don't get lost in the pipeline.
LRTV Custom TV
We Can Make the World More Sustainable

11|29|16   |     |   (0) comments


GeSI is a global e-Sustainability Initiative organization bringing together 40 big multinational companies around the world. According to GeSI's report, information and communication technology can make the world more sustainable. Luis Neves, chairman of GeSI, shared with us his opinion at Ultra-broadband Forum (UBBF2016).
LRTV Custom TV
Finding a New Way to Engage Customers & Drive Revenue

11|29|16   |     |   (0) comments


Mobile revenues are declining. Digicel, a player in the Caribbean telecommunications/entertainment space, has found a new way to engage customers and drive revenue. John Quinn, CTO of Digicel, shared with us its story at Ultra-broadband Forum (UBBF2016)
LRTV Custom TV
Do You Really Need Gigabit Infrastructure?

11|29|16   |     |   (0) comments


Altibox is the biggest fiber-to-the-home (FTTH) player and the largest provider of video and TV in Norway. They started out with zero customers in 2002. Now they have close to half a million households and companies attached to their FTTH business. Nils Arne, CEO of Altibox shared with us their story and insight on 5G at Ultra-broadband Forum (UBBF2016).
LRTV Custom TV
BTís Openreach Strategy & Its Updates in 2016

11|29|16   |     |   (0) comments


A lot of developments at Openreach this year in terms of strategy and planned investments. Peter Bell, CIO of Openreach BT, shared with us the updates of Openreach at Ultra-broadband Forum (UBBF2016).
LRTV Custom TV
ITU: The Broadband Is Our Future

11|29|16   |     |   (0) comments


At Ultra-broadband Forum, Houlin Zhao, Secretary General of ITU, discussed how important it is for countries, companies and everybody to be working together to help to build the broadband and digital economies (UBBF2016).
LRTV Custom TV
Tackling 5G in Dallas

11|28|16   |     |   (0) comments


Here are our highlights of the 5G North America show in Dallas, Texas with Light Reading's Dan Jones.
LRTV Interviews
Cox Prepping for Virtualization Trials

11|14|16   |     |   (0) comments


In this video interview, Cox's Jeff Finkelstein discusses MSO's plans to test managed business services in early 2017 and tackle Distributed Access Architectures.
LRTV Custom TV
Drivers & Potential of NGP

11|11|16   |     |   (0) comments


ETSI has created an Industry Specification Group to work on Next Generation Protocols (NGP ISG), looking at evolving communications and networking protocols to provide the scale, security, mobility and ease of deployment required for the connected society of the 21st century. The NGP ISG will identify the requirements for next generation protocols and network ...
LRTV Custom TV
Huawei IP 2020 for Future Networks

11|11|16   |     |   (0) comments


Future Networks should satisfy many requirements such as high throughput, extremely low latency, flexible mobility, intrinsic security, networking automation, and so forth. The Chief Architect of Huawei Future Networks addresses a holistic solution, i.e., IP 2020, to achieve these requirements for various future life scenarios (e.g., autonomous driving, tactile ...
LRTV Custom TV
Digital Object Architecture

11|11|16   |     |   (0) comments


Digital Object Architecture provides a basic information infrastructure that can facilitate interoperability between or among different systems, processes, and other information resources, including different identity management systems. Digital objects are networked objects that are named by digital object identifiers and instantiated by an infrastructure service ...
LRTV Custom TV
BT's Openreach Has High Hopes for Long-Reach VDSL

11|11|16   |   06:04   |   (0) comments


Peter Bell, Network Portfolio CIO at BT's access business Openreach, talks about the operator's trial of a new broadband access technology called Long Reach VDSL.
Upcoming Live Events
December 6-8, 2016, The Westin Excelsior, Rome
May 16-17, 2017, Austin Convention Center, Austin, TX
All Upcoming Live Events
Infographics
Hot Topics
AT&T Debuts DirecTV Now on New Video Platform
Mari Silbey, Senior Editor, Cable/Video, 11/28/2016
Apple Seeds 5G? Seeks 'Multi-Gigabit' Chip Designer
Dan Jones, Mobile Editor, 11/30/2016
Altice Plans FTTH for Entire US Footprint
Iain Morris, News Editor, 11/30/2016
Altice FTTH Bill Could Hit Almost $9.6B in US
Iain Morris, News Editor, 12/1/2016
Samsung Bows to Investors, Considers Revamp
Iain Morris, News Editor, 11/29/2016
Like Us on Facebook
Twitter Feed
BETWEEN THE CEOs - Executive Interviews
Eyal Waldman, CEO of Mellanox Technologies, speaks to Steve Saunders, CEO of Light Reading, for an exclusive interview about the 100 GB cable challenge, cybersecurity and much more.
Join us for an in-depth interview between Steve Saunders of Light Reading and Alexis Black Bjorlin of Intel as they discuss the release of the company's Silicon Photonics platform, its performance, long-term prospects, customer expectations and much more.
Live Digital Audio

Even when there's a strong pipeline of female talent in the comms industry, it tends to leak all the way to the top. McKinsey & Company says women experience pipeline leakage at three primary points: being unable to enter, being stuck in the middle or being locked out of the top. Each pipeline pain point presents its own challenges, but also opportunities to stop the leak. Wireless operator Sprint is making a conscious effort to improve its own pipeline from new recruits to the C-suite, and it wants the rest of the industry to do the same. In this Women in Comms radio show, WiC Board Member and Sprint Vice President of Enterprise Sales Nelly Pitocco will give us her take on the industry's pipeline challenges. Pitocco, who joined Sprint in May and has spent 20 years in the comms industry, will also offer solutions, share how Sprint is tackling the challenge within its own organization and take your questions live on air.