When AlphaStaff acquired another Florida-based HR staffing company in 2009, it grew its business from handling HR services for 6,000 people to more than 80,000 staffers. The extra business completely overwhelmed its LeftHand storage area network and its enterprise resource planning (ERP) system. Plus, in the five years since they had bought the LeftHand system, the company's data had grown from a manageable 1 TB to over 60 TB of storage.
Rahner knew he had a problem. Addressing capacity and then performance were his major concerns. Employees were complaining that they could not access the ERP and business intelligence applications without delays. These two applications were the lifeblood of AlphaStaff's business, allowing them to process payroll and manage an employee's benefits. In addition, Rahner and his team had started virtualizing the servers within AlphaStaff using VMware and in doing so, added an additional tax on the storage system.
[ Surrounded by data? Growing storage without end? Demands from users for fast access? Endless retention policies? Here's how to cope. The Storage Problem You Can't Ignore. ]
"Everything was getting virtualized and we were getting the most out of our hardware," says Rahner. "I started to realize, though, that the weakest link was capacity. And, now that has taken a backseat to disk speed. We started saturating the network and were having bandwidth issues."
So Rahner started looking for a storage system to replace the LeftHand system he had. He looked at EMC and NetApp and finally chose Compellent, which was 60% faster than his previous storage area network (SAN). Then he connected his legacy ERP and business intelligence applications to the Compellent Storage Center SAN. It came equipped with three tiers of storage: solid state drives (SSDs), 15,000 RPM Serial Attached SCSI (SAS) drives, and 10,000 RPM SAS drives.
"We are moving our ERP system and business intelligence system over to solid state drives for one reason: latency," said Rahner. "When you are dealing with very high transactions or applications that are very database-intensive and require lots of serving of disk, solid state drives make a major difference."
As a result of the SSDs, "we had our latency go from 10 milliseconds a transaction at 10,000 [I/O operations per second] to one millisecond overnight," said Rahner. Through testing of the ERP system with the Compellent Storage Center SAN, Rahner determined that there was an 80% performance improvement for the ERP system.
Rahner's use of SSDs in his Compellent Storage Center SAN also garnered other business benefits.
"Because everything is virtualized and running on VMware, we were seeing performance from [our business intelligence application] that was less than optimal. Our customers were waiting 10 seconds or more to get information they needed. Going to SSDs made a world of difference."
Deni Connor is founding analyst for Storage Strategies NOW, an industry analyst firm that focuses on storage, virtualization, and servers.
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