Is FCoE faster than Fibre Channel? Who knows? Just run your own tests

Cisco camp takes exception to Brocade-funded Evaluator Group study


The Cisco Fibre Channel over Ethernet (FCoE) supporters' club has taken grave exception to what it views as a deeply flawed Evaluator Group study, funded by Fibre Channel (FC) enthusiasts Brocade, which showed FC was faster than FCoE.

FCoE supporters say the study shows no such thing and lambasted both the Evaluator Group and the "churnalists," as they term them, who reported it without pointing out the flaws as they perceive them, in the study.

A Twitter storm followed the reporting of the report. One result was a blog by Cisco's J Metz, Strategic Product Manager, Storage and Unified Fabric at Cisco Systems, in which he tore the study to pieces, talking about "the ugly spectre of blatant dishonesty that exposed a disturbing trend of vendor-media collusion that I feel harms people."

Metz also laid into trade press for not evaluating the study properly: "[The] trade press is supposed to read and evaluate these studies for merit and summarise to a more general audience. They are also supposed to be more educated about the topic than their readers (after all, why bother writing about it otherwise?) and provide a sense of context that may offset the inherent bias which naturally accompanies the study."

Should this trade press person defend his reporting? (Why not? - Ed.) I doubt very much whether I'm more educated on the general topic of FC and FCoE than many of my readers. I just get to hear stuff sooner and report it, hopefully in a neutral enough way and, sometimes, with snarky hints about the provenance of things.

Anyway, back to Metz' criticism; "If you ever want a prime example of how not to do a research project, this is Exhibit A."

His main points are:

  • The study uses the phrase “Gen 5, 16Gbps FC switch.” Gen 5 is Brocade’s marketing term for their latest platforms; it is not an industry standard term, despite its recent adoption by QLogic and Emulex
  • Anti-Cisco bias in text: "Actual latencies would likely be higher for an all-Cisco deployment using FCoE… connected to Cisco MDS switch, than the tested environment.” But MDS' switch wasn't used in the testing so why mention it?
  • Use of Brocade marketing brochure text
  • Inexpert Evaluator Group testers: "The setup of the FCoE environment required approximately 8 hours of time. Several issues were encountered while configuring the UCS equipment. Additional assistance was requested from a VAR with certified UCS engineers.”
  • Flawed test set up with FCoE using UCS servers and FC HP servers. Why vary the servers?
  • Also FC was configured end-to-end, whereas two FCoE 10gigE came from the servers to a Cisco switch and then uplinked to a Brocade FC switch via two 8Gbit/s FC lines, that could not be aggregated, to make a logical 16Gbit/s FC link travelling to target arrays using FC. Why was this throttling done? Why not end-to-end FCoE?
  • The test design had a 10gigE link get converted to an 8Gbit/s FC link which then went into a 16GBNit/s link. Metz says: "Whenever you put information on a wire it needs to be encoded, and all three versions have different encoding schemes, which means that from a throughput perspective, you have a massive bottleneck smack dab in the middle."

Metz considers that most of the reported under-performance by FCoE could be accounted for by this bottleneck. There's more; read the blog to see it.

Metz is seriously displeased about the study. "The real concern I have is that if something this bad, this egregious, isn’t called out by the so-called “watchdogs of technology,” what hope do the non-technical and the uninitiated have to find out the truth?"

He continues: "All in all, this study reeks of desperation on Brocade’s part, that they are willing to throw caution (and logic) to the wind, paying for – and publishing – some of the worst testing I’ve ever seen in my life, and got other media firms to promote it."

Russ Fellows of the Evaluator Group emailed The Register and said a Q and A about the study was available (here). It sets the scene for the testing.

"As an independent analyst firm,” says the Q&A, “Evaluator Group was engaged by Brocade to conduct a comparison of two environments, a Cisco UCS with FCoE server connections and an HP BladeSystem with Fibre Channel server connections, both connected to Fibre Channel storage."

Then there was this statement:

The objective of the test was to compare the impact of deploying the latest generation Flash storage on high performance enterprise applications in virtual server environments. A 16 Gb Fibre Channel flash storage array was selected as the storage target, and HP c7000 and Cisco UCS were selected for the blade servers given their market share leadership.

Based on the most common deployment models with shared storage for each solution, UCS servers used FCoE to connect to a Fibre Channel SAN while end-to-end Fibre Channel connectivity was used on the HP c7000, with both connecting to the same solid state Fibre Channel storage array. The objective was to understand how the two different architectures would impact the application benchmarks using the same storage.

The doc says: "The configurations were carefully chosen to be as fair as possible; ensuring storage network limitations were equal for both configurations."

Metz would, judging by his blog statements above, vehemently disagree with this statement.

It's a fairly short Q and A and, reading between the lines, you might think the Evaluator Group wished it had not gotten into a shitstorm over this study.

Which leaves us where?

If you are evaluating a choice of Fibre Channel or FCoE do not rely on vendor-funded studies. Run your own pilot test and draw your conclusions from that. ®

Similar topics

Narrower topics


Other stories you might like

  • DigitalOcean tries to take sting out of price hike with $4 VM
    Cloud biz says it is reacting to customer mix largely shifting from lone devs to SMBs

    DigitalOcean attempted to lessen the sting of higher prices this week by announcing a cut-rate instance aimed at developers and hobbyists.

    The $4-a-month droplet — what the infrastructure-as-a-service outfit calls its virtual machines — pairs a single virtual CPU with 512 MB of memory, 10 GB of SSD storage, and 500 GB a month in network bandwidth.

    The launch comes as DigitalOcean plans a sweeping price hike across much of its product portfolio, effective July 1. On the low-end, most instances will see pricing increase between $1 and $16 a month, but on the high-end, some products will see increases of as much as $120 in the case of DigitalOceans’ top-tier storage-optimized virtual machines.

    Continue reading
  • GPL legal battle: Vizio told by judge it will have to answer breach-of-contract claims
    Fine-print crucially deemed contractual agreement as well as copyright license in smartTV source-code case

    The Software Freedom Conservancy (SFC) has won a significant legal victory in its ongoing effort to force Vizio to publish the source code of its SmartCast TV software, which is said to contain GPLv2 and LGPLv2.1 copyleft-licensed components.

    SFC sued Vizio, claiming it was in breach of contract by failing to obey the terms of the GPLv2 and LGPLv2.1 licenses that require source code to be made public when certain conditions are met, and sought declaratory relief on behalf of Vizio TV owners. SFC wanted its breach-of-contract arguments to be heard by the Orange County Superior Court in California, though Vizio kicked the matter up to the district court level in central California where it hoped to avoid the contract issue and defend its corner using just federal copyright law.

    On Friday, Federal District Judge Josephine Staton sided with SFC and granted its motion to send its lawsuit back to superior court. To do so, Judge Staton had to decide whether or not the federal Copyright Act preempted the SFC's breach-of-contract allegations; in the end, she decided it didn't.

    Continue reading
  • US brings first-of-its-kind criminal charges of Bitcoin-based sanctions-busting
    Citizen allegedly moved $10m-plus in BTC into banned nation

    US prosecutors have accused an American citizen of illegally funneling more than $10 million in Bitcoin into an economically sanctioned country.

    It's said the resulting criminal charges of sanctions busting through the use of cryptocurrency are the first of their kind to be brought in the US.

    Under the United States' International Emergency Economic Powers Act (IEEA), it is illegal for a citizen or institution within the US to transfer funds, directly or indirectly, to a sanctioned country, such as Iran, Cuba, North Korea, or Russia. If there is evidence the IEEA was willfully violated, a criminal case should follow. If an individual or financial exchange was unwittingly involved in evading sanctions, they may be subject to civil action. 

    Continue reading
  • Meta hires network chip guru from Intel: What does this mean for future silicon?
    Why be a customer when you can develop your own custom semiconductors

    Analysis Here's something that should raise eyebrows in the datacenter world: Facebook parent company Meta has hired a veteran networking chip engineer from Intel to lead silicon design efforts in the internet giant's infrastructure hardware engineering group.

    Jon Dama started as director of silicon in May for Meta's infrastructure hardware group, a role that has him "responsible for several design teams innovating the datacenter for scale," according to his LinkedIn profile. In a blurb, Dama indicated that a team is already in place at Meta, and he hopes to "scale the next several doublings of data processing" with them.

    Though we couldn't confirm it, we think it's likely that Dama is reporting to Alexis Bjorlin, Meta's vice president of infrastructure hardware who previously worked with Dama when she was general manager of Intel's Connectivity group before serving a two-year stint at Broadcom.

    Continue reading
  • Lithium production needs investment to keep pace with battery demand
    Report says $42b will need to be poured into industry over next decade

    Growing demand for lithium for batteries means the sector will need $42 billion of investment to meet the anticipated level of orders by the end of the decade, according to a report.

    Lithium is used in batteries that power smartphones and laptops, but there is also rising use in electric vehicles which is putting additional pressure on supplies.

    The report, Benchmark Mineral Intelligence, predicts that demand will reach 2.4 million tons of lithium carbonate equivalent by 2030, roughly four times the 600,000 tons of lithium forecast to be produced this year.

    Continue reading

Biting the hand that feeds IT © 1998–2022