Corona Norco Unified School District in Norco, Calif., made the move to flash storage about two years ago when the district transitioned its student computer labs to virtual desktop infrastructure (VDI).
Brian Troudy, director of networking and infrastructure, says the district now has 3,500 LG zero clients running in labs across 49 schools in a district that has about 55,000 students and 5,000 teachers and staff.
“We were looking to replace and streamline the management of desktops in the labs, plus we needed more processing power for VDI,” Troudy says. “Our old system simply couldn’t run 300 to 400 concurrent VDI sessions, and the result was the students wouldn’t use the VDI system.”
Now, the district runs a Nimble storage array for its VDI, file server, SQL databases and virtualized servers. Practically everyone uses VDI now, and users experience response times of under a millisecond on database queries.
The Nimble system has a unique architecture in which the system stores all the data in both flash and spinning disks. Reads (queries) are run in flash, and the data also resides as a redundant backup on spinning disks. To improve response times, the system sends frequently accessed data to the front of the cache on the flash drives.
“It’s made a night-and-day difference,” says Troudy, who adds that he now has the storage infrastructure in place to expand VDI across the district.
Eric Burgener, research director for IDC’s storage practice, says that while hybrid arrays remain popular with many organizations, ultimately all-flash units will replace the hybrid products currently offered by manufacturers. Recent IDC research shows that 18 percent of organizations already use all-flash arrays, while 23 percent use hybrid arrays. Another 37 percent use existing spinning disks with flash drives added as cache.
“People move slowly when mission-critical applications are at stake. Plus, there’s a comfort level with spinning disks,” says Burgener. “Overall, we expect the transition to all-flash for primary storage environments to take five to seven years.”
At Putnam City Schools in Oklahoma City, the district runs 2.4 terabytes of flash as the fastest tier in a three-tier system.
“We use profiles to allow access to the tiers; data that is not sensitive to access times is not allowed onto the flash tier,” explains Cory Boggs, executive director of IT services.
Boggs says the district uses the flash mostly to absorb database writes and to store the most frequently accessed data. This includes Oracle databases, Microsoft Exchange and the student information system data.
“It is critical that the databases in which the student information system data reside responds quickly, as it is written to thousands of times an hour by thousands of users — teachers, secretaries, administrators, principals and the student accounting staff,” Boggs adds.
Multiple Flash Flavors
Eric Burgener, research director for IDC’s storage practice, outlines the three prevailing flash storage options available today.
All-flash arrays: Products such as the EMC XtremIO and IBM FlashSystem 840 are geared to mission-critical database and business applications that need the fastest processing available.
All-flash configurations of hybrid arrays: Manufacturers target these devices for organizations that seek more mature data services in an all-flash array, such as snapshots, clones, replication, thin provisioning, encryption and quality of service. The Hitachi Data Systems Hitachi Accelerated Flash Storage offers a good example.
Hybrid systems: Systems such as the EMC VMAX offer some flash capabilities for mission-critical applications and spinning disks to offload shared drives or documents.