I was always a bit skeptical of Skyera's skyHawk, a 1u, single-controller system. While it's a good value and delivers up to 44 Tbytes, I was uncomfortable with the single point of failure. I also wondered whether the built-in 10-Gbps Ethernet switch was really necessary.
Sure, there are applications like OLAP and VDI where the data's replaceable, and at $3 per gigabyte, skyHawk is a price leader, but if I'm paying the all-solid-state price, I want redundancy.
Enter the skyEagle, a dual-controller 1U storage appliance that comes with up to a whopping 250 Tbytes. Where skyHawk was primarily an iSCSI and NFS appliance, skyEagle adds Fibre Channel support, making it more attractive to mainstream corporate users. Skyera continues to be a price leader, as well, selling skyEagle for under $2 per gigabyte (which comes to just under a million dollars for a maxed-out system).
[As the SSD market begins to consolidate, who's poised for victory? Howard Marks places some bets in "SSD Vendors: Which Will Win?."]
For those that don't need 250 Tbytes, skyEagle also has models with 65 and 125 Tbytes. If you need more storage, the company promises a version with 500 Tbytes later this year. Other specs include 5 million IOPs, 800 watts operating, and 16 dual-mode 10-Gbps Ethernet/16-Gbps Fibre Channel ports.
All Skyera systems use data reduction technology to extend the life of the flash by reducing writes and increasing capacity. For a typical application mix, users will get well over a petabyte of useable capacity from the 500-Tbyte model--even after the overhead for data protection.
Having spent most of my career as a consultant in New York, I've seen data centers on the 38th floor of an office building that are completely full. In that kind of environment, density becomes an important feature of your storage system.
At 250 and soon 500 Tbytes per rack unit, skyEagle is by far the densest storage system on the market. Most other vendors' highest density systems put 60 3.5-inch disk drives in a 4u box. Even with 4-Tbyte drives, that's just 60 Tbytes per rack unit.
Density is also a big selling point in the government/military market. A P3 Orion spy plane, for example, collects data through an array of sensors. On some missions, on-board storage capacity is the limiting factor. Put more capacity in the limited space of the airframe and you can collect more intelligence.
Skyera manages to squeeze that much flash in a 1u box by bypassing traditional SSDs and building its own flash controllers and modules. These modules, which look like overgrown DIMMS, are hot-swappable. But that means sliding the system partway out of the rack and sticking your hands inside, so I'm sure many users won't risk it.
My friend and fellow storage analyst Robin Harris and I had a battle of the blog posts a couple of years ago (here, here and here) over whether all-flash arrays should use SSDs or whether vendors should develop their own flash controller and modules to bypass the SAS/SATA bottleneck talking to traditional SSDs.
Robin argued for custom modules. I figured you could get plenty of performance out of SSDs. I also argued that faster speed to market and the ability to leverage merchant controller enhancements as they came around was worth any performance disadvantage using SSDs might cause.
Now Skyera comes around to show me that building your own modules can get you more than another 100,000 IOPS density. Of course, Skyera's team knows a little about building flash controllers, having been the brains behind the Sandforce controller before LSI bought Sandforce. Skyera seems to be the exception that proves the rule that startups should pay attention to their software and leave flash controller design to the professionals.