Feeds

QLogic: Software FCoE can't cut it

Intel indifference

  • alert
  • submit to reddit

Bridging the IT gap between rising business demands and ageing tools

Interview What does a HW Fibre Channel over Ethernet (FCoE) vendor think of Intel's software FCoE stack? We asked QLogic's Host Solutions Group through Henrik Hansen, its European marketing director.

Intel has released an openly available Fibre Channel over Ethernet (FCoE) software stack so users can send and receive messages to Fibre Channel access storage systems without having to use FCoE converged network adapters (CNAs), specialised Ethernet interface cards with FCoE functions added.

The CNA supplier thinking is, generally, that servers should run applications and offload storage I/O processing to peripheral cards.

So El Reg asked Hansen about QLogic's position on Intel's SW FCoE. We've edited the replies to bring out what we think are the essential points. The resulting Q&A session has some QLogic marketing puffery in it but the general message is clear enough: software FCoE can’t cut it in the data centre.

El Reg: What are the main differences between Intel's open source FCoE software used on a standard Ethernet NIC and QLogic's FCoE-capable CNA?

Henrik Hansen: Host systems using Intel or NICs running FCoE software initiators will be limited in scalability as storage workload processing by the CPU can command up to 70 per cent of the CPU resources, leaving little for application processing or for virtual machines.

QLOgic HW vs SW FCoE chart

A CNA on the other hand offloads FCoE to the adapter and requires between 4-10 per cent of the CPU to process the same storage workloads. FCoE software initiators have limited O/S support (currently Linux only), with Microsoft not yet not commenting on a support time frame, and issues within the way Hypervisors and the O/S exchange protocol processing. The current implementation of SW initiators will not work. Changes must first be made in the SW architecture for hypervisor support.

SW initiators will require years of development and real world deployment before they are ready for enterprise-wide storage deployments: Intel currently only has five vendors qualified while QLogic has over 80 qualified vendors with thousands of products.

We have support for OEM partitioning (HPs Flex-10, IBM's Virtual Fabric Adapter and QLogic’s own, switch-agnostic NPAR (with embedded layer 2 switching)) including QoS to segment networks and improve application performance compared to Intel’s limited VLAN partitioning.

El Reg: The HW CNA vendors say they offer much better management facilities as well. Moving on, what effect do you think Intel's FCOE software will have on the storage networking market?

Henrik Hansen: QLogic does not believe data centre administrators will trust their enterprise storage application to an unproven technology that is receiving limited endorsment by storage manufactures. It will take many years for [Intel's SW FCoE to] receive pervasive storage qualification, OS and hypervisor support. With most of the OEMs supporting proven storage driver stacks, it will in fact stall acceptance of S/W initiators.

El Reg: With multi-core X86 processors do you really need a dedicated FCoE engine on a CNA instead of using a standard Ethernet NIC?

Henrik Hansen: Virtual Machine (VM) density continues to grow, and this will have a material effect on servers attempting to run software initiators and VM’s simultaneously. In order to efficiently scale these servers, CPU [cycles] must be conserved for the hypervisors, and not used for processing storage I/O.

El Reg: As there are now more software iSCSI initiators than iSCSI-capable Ethernet interface card initiators, won't the FCOE market follow iSCSI, with the majority of FC ports on servers being driven by software FCoE code stacks and not CNAs?

Henrik Hansen: iSCSI initiators have mainly been adopted by small to medium business (SMB) where enterprise reliability is not as much of a concern as it is within enterprise storage market.

A new dichotomy is occurring within the data centre; this is being driven by virtualisation and convergence onto one wire. Implementing both with an FCoE software initiator will starve the CPU and limit the scalability of virtual machines as well as throughput requirements for storage-demanding applications.

In order to scale efficiently within this new dichotomy, CPU resource will be better used serving VMs and applications than processing of I/O.

Build a business case: developing custom apps

Next page: Summing up

More from The Register

next story
BBC goes offline in MASSIVE COCKUP: Stephen Fry partly muzzled
Auntie tight-lipped as major outage rolls on
You! Pirate! Stop pirating, or we shall admonish you politely. Repeatedly, if necessary
And we shall go about telling people you smell. No, not really
Airbus promises Wi-Fi – yay – and 3D movies (meh) in new A330
If the person in front reclines their seat, this could get interesting
UK Parliament rubber-stamps EMERGENCY data grab 'n' keep bill
Just 49 MPs oppose Drip's rushed timetable
There's NOTHING on TV in Europe – American video DOMINATES
Even France's mega subsidies don't stop US content onslaught
Samsung threatens to cut ties with supplier over child labour allegations
Vows to uphold 'zero tolerance' policy on underage workers
Dude, you're getting a Dell – with BITCOIN: IT giant slurps cryptocash
1. Buy PC with Bitcoin. 2. Mine more coins. 3. Goto step 1
ITC: Seagate and LSI can infringe Realtek patents because Realtek isn't in the US
Land of the (get off scot) free, when it's a foreign owner
prev story

Whitepapers

Seven Steps to Software Security
Seven practical steps you can begin to take today to secure your applications and prevent the damages a successful cyber-attack can cause.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.