Feeds

IBM multi-petabyte cloud defies XIV storage

How does it scale that much?

  • alert
  • submit to reddit

Build a business case: developing custom apps

Comment With its Smart Business Storage Cloud, IBM says we have its GPFS and XIV being used to build a system capable of multiple petabytes of capacity and supporting billions of files with high-performance computing-like I/O performance. But XIV has a maximum usable capacity of 79TB.

We can envisage an IBM BladeCenter server set running the GPFS (General Parallel File System) connected to an XIV rack, but this seems utterly unbalanced. There is a BladeCenter/GPFS setup capable of handling multiple petabytes and billions of files on the one hand, hooked up to an XIV array that can only hold 79TB and hundreds of thousands or single digit millions of files of any size on the other. What is going on? How will this work?

To get XIV storage up to the multi-PB level IBM has either to scale up XIV, scale out XIV, or do it indirectly and scale out server nodes with attached XIV arrays. Which is it going to use?

Scaling up XIV

XIV arrays use 1TB drives. Let's bring in 2TB drives and make the capacity 158TB. It's still nowhere near enough. If we assume a multi-petabyte capability means 10PB then we would need 64 times as many drives as it could use today. That means a 120X increase in capacity as we continue scaling towards 20PB.

It seems extremely unlikely that IBM is going to announce a souped-up XIV product with a 64X or 120X increase in capacity. The backplane and controller-drive enclosure interconnect technology would be awesomely difficult to design, engineer and develop.

Scaling out XIV

How about clustering XIV arrays? Can we do that? The XIV, with its 21 nodes, is already internally clustered, IBM describing it thus: "The XIV system is based on a grid of standard, off-the-shelf hardware components connected in any-to-any topology by means of massively paralleled, non-blocking Gigabit Ethernet." Devising a cluster interconnect and node software to keep things on track for an already clustered product is like engineering a cluster of clusters.

To scale to, say, the 10PB level, an XIV array using 2TB drives and maxing out at 158TB would need 64 nodes. A 64-node interconnect capable of scaling to higher node levels is perfectly feasible.

Isilon and Exanet make NAS clusters that go past the 1PB capacity level. Isilon can have up to 96 nodes in a scale-out design using 20Gbit/s InfiniBand. So we could envisage some way of scaling out XIV capacity by linking XIV nodes together with InfiniBand and adding functionality to XIV software to enable the nodes to co-operate.

However, scaling up XIV in this way would need a lot of XIV development work. Suppose we take a different tack.

Build a business case: developing custom apps

More from The Register

next story
Sysadmin Day 2014: Quick, there's still time to get the beers in
He walked over the broken glass, killed the thugs... and er... reconnected the cables*
Auntie remains MYSTIFIED by that weekend BBC iPlayer and website outage
Still doing 'forensics' on the caching layer – Beeb digi wonk
Microsoft says 'weird things' can happen during Windows Server 2003 migrations
Fix coming for bug that makes Kerberos croak when you run two domain controllers
Cisco says network virtualisation won't pay off everywhere
Another sign of strain in the Borg/VMware relationship?
VVOL update: Are any vendors NOT leaping into bed with VMware?
It's not yet been released but everyone thinks it's the dog's danglies
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
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.
Backing up Big Data
Solving backup challenges and “protect everything from everywhere,” as we move into the era of big data management and the adoption of BYOD.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.