Poor Performance Leads To Deployment Of SSD Technology for Aspirus

In the dynamic, growing industry of health care, IT systems increasingly impact how companies perform. Aspirus of central Wisconsin found that its main records management application was being bogged down by poor performance. In response, the firm decided to become an early user of Solid State Disk (SSD) technology, and the change had a dramatic impact on its system performance.

Aspirus has 4,300 employees, delivers services via five hospitals and 35 to 40 clinics in 14 Wisconsin counties and Michigan's Upper Peninsula. The company's data center in Wausua supports a mix of servers. IBM AIX P series servers run Health Outcomes Sciences Epic healthcare applications, an integrated hospital and clinic system. Aspirus has 200T of storage, arranged in a hierarchical manner, and their data requirements have grown from 20 to 30 percent annually. This comes from expansion of its main systems as well as adding more clinics and hospitals to its network.

For the past few years, performance with the Epic system was scattershot. "We were having random latency issues and I/0 problems whenever users worked with the GUI on the front-end or computing intensive back-end functions, such as importing data," explained Tom Whalen, IT Server and Storage Infrastructure Team Leader at Aspirus. In response, the company would fine-tune its disk system and servers, and the problems would disappear for a while, but then they would reoccur. The process was complicated by vendors who would engage in rounds of finger-pointing.

Aspirus has been an EMC customer since the Epic system was purchased in 2004. That deployment was the health care organization's first Storage Area Network. Since that time, the company decided to stick with EMC because it did not want to take on the added management complexity that can come from working with products from a number of different storage vendors.

At the end of 2007, Aspirus was talking with EMC when the vendor mentioned that it was designing enterprise-level SSDs. Aspirus was interested because it thought the new approach might address its performance issues. Even though flash storage came at a 40 percent premium compared to disk storage, they expected the possible performance boost to offset the cost difference. In Dec. 2008, they received the first tray of flash drives in North America for EMC's Clarion system. "EMC didn't even have part numbers for the drives yet," Whalen joked.Aspirus spent about five months shaking out the drives and trying to determine how to maximize their performance. The first step was gaining a thorough understand of its application storage characteristics. The Epic application is a read-heavy application. While flash may not be well suited to write-heavy applications, it can do a good job speeding up read-heavy applications.

However, there were some deployment issues. Quickly, the server infrastructure became more of a bottleneck than the drives themselves, and the company was reaching the point where it was beginning to max out its host-bus adapters. Also, a few of the drives failed because of firmware issues. The drives were being flagged as having media errors even though that was not the case. EMC was responsive to that problem. The company shipped replacement drives over night, so no data was corrupted, and it issued a patch to the Clarion system.

Over all, the SSDs have proven to be quite manageable. The Clarion system does a good job of searching for soft-media errors and disks that might be going bad. It will do an integrity check against the whole SAN, validate the parities and make sure there are no media errors. If problems arise, Aspirus is notified by email or text message, and "sometimes, the EMC engineer walks in with the new drive before I even know there is a problem," stated Whalen.

When Aspirus hooked up the flash drive to it Epic system, it saw performance improvements of 200-300 percent compared to a very elaborate RAID 10 mix of four-plus-four, and two-plus-two disks built out over 24 and 36 drives. The Epic system has been functioning much better and the random latency and I/O problems have disappeared. "SSDs may not make sense for all applications but they have proved beneficial with our health care system," concluded Whalen.