Leary explains that Nimble has taken a hybrid approach to its storage architecture. Dubbed Cache Accelerated Sequential Layout Architecture (CASL), it combines the performance of flash memory and low-cost disk capacity. CASL takes a new approach to laying out data, by taking random writes coming into the system and writing them on a new location on disk sequentially, making more efficient use of low-cost disk, he explained. "We turn slow disk into something that's very fast because we're not asking it do something that it's bad at," Leary says.
Meanwhile, data that is likely to read again quickly, such as new email messages in Microsoft Exchange, is put on flash because it's good at performing reads fast, says Leary. Frequently requested data sits on the flash layer but also resides on disk. "We've purpose-built our fundamental architecture around the fact that there's always going to be flash and disk in our system."
Marks says many vendors have bolted on flash to existing storage systems, but there are limitations to how far that can go because they weren't designed to take advantage of flash from inception. "The way you design a system for spinning disks and the way you design a system for flash are very different," he says. "Trying to make one system that does both well while remaining backwards compatible is too hard. Eventually, you have to start with a clean sheet of paper."
He says another unique differentiator for Nimble is its efficient snapshot system built into its file system, which lets the system use snapshots as backups. "It's what makes it use flash effectively, and it's what makes it use snapshots effectively."
Foster Pepper, a Seattle-based general practice law firm with 350 employees and a second location in Spokane, Wash., originally adopted Nimble because it was struggling to back up its discovery data. "We were running into 72-plus hour backup windows," says IT director Lucas Clara.
After adopting Nimble for that purpose alone, the firm moved its entire storage infrastructure over from EMC and has seen improved performance in other areas such as its Microsoft Exchange environment and data warehousing. "We've never run into any storage bottleneck since we've implemented Nimble," Clara says.
Foster Pepper standardized on Nimble two years ago to run its own private cloud. The firm has eight Nimble units in production--both CS240G and CS260G models--which run in its virtualization environments and provide its core infrastructure for storage, with 200 Tbytes of data.
Clara says Foster Pepper does a lot of litigation work that involves e-discovery, which has the potential to bring in a lot of data. Because the amount of data is unpredictable and very case-centric, it's hard to plan out storage capacity. "Today it may be no growth; tomorrow it may be several terabytes of data that comes in."
With Nimble's new storage architecture, Foster Pepper could purchase an additional shelf that includes disk and flash to increase capacity or address performance by clustering more controller units or increasing the cache cards on the system. "It's modular, based on what my business needs happen to be," says Clara. Prior to adopting Nimble, he would have to "drastically" over-provision.
Leary says existing customers can have a new array or shelf shipped to them within a couple of business days, if necessary, and have them up and running within 30 minutes.
Nimble's CS400 series arrays, ES-Series expansion shelves and flash expansion options will be available in the third quarter; Nimble OS 2.0 will be available in the fourth quarter. Pricing for the CS400 series array starts at $80,000, while pricing for CS200 series starts at $38,000. Expansion shelves start at $35,000, with 15 Tbytes capacity and up.