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After a SAN upgrade failed to solve its latency problem with a vital medical application, the Anchorage Neighborhood Health Center achieved the desired results with server-based flash and PernixData FVP software.
The non-profit ANHC provides primary medical, dental and behavior health sciences care for thousands of patients per year. Following a data center consolidation and increase in server virtualization, the agency experienced latency with the electronic health records (EHR) system used to access patient records.
"Our primary problem was performance. The pages would take three to five seconds to load," said Mike Lane, the systems administrator responsible for ANHC's virtualized infrastructure. "That doesn't seem that bad but we have medical staff clicking on multiple tabs and it adds up to a lot of frustration."
In 2012, ANHC consolidated its two data centers into its current facility in midtown Anchorage. ANHC redesigned its IT infrastructure to include server virtualization and a storage upgrade to an EMC VNXe 3300. Lane said ANHC's latency problem came about after server virtualization made it easy to spin up virtual machines as needed.
ANHC's EHR provider determined the read performance on the EHR application was running between six and eight milliseconds.
"They said that was unacceptable," Lane said. "We needed to get below 2 milliseconds."
Lane said ANHC spent $20,000 to upgrade its VNXe 3300, adding an expansion shelf with 15 additional disk drives for a RAID-10 implementation. That improved performance by about 2 milliseconds, but was still falling short of the latency required.
"It was nowhere near the improvement we thought we would get," he said. "We still didn't get the sub-2 milliseconds we needed for the user interface."
ANHC decided to try and fix the problem at the server level instead. Lane's team tested PernixData FVP software and off-the-shelf Samsung solid state drives (SSDs) on Dell servers. FVP software pools server-based flash and RAM to speed file and block storage and boost the performance of virtual machines. The application allows any server that runs the software to access the resources of any other host in a cluster and replicates writes across the cluster hosts to ensure fault tolerance.
"PernixData said if we bought two SSDs and put them in two physical servers, we would get the improvement we needed," Lane said. "We looked at it from a standpoint of skepticism because we had just spent $20,000 [on its SAN]."
The test deployment yielded great results, however.
"The host had to be rebooted to install the host extension for PernixData," Lane said. "It's not a difficult process if you are an experienced administrator in VMware. The whole process took two hours to set up. We turned on the console and it took a couple of hours to build enough cache to show a difference; but in a day we were below the 2 millisecond threshold. It cost about $300 for the SSDs and we downloaded the PernixData FVP software."
Lane said ANHC purchased 1 TB of consumer-grade SSDs for each of three Dell PowerEdge R620 servers, and that its EHR application was running at an average latency of 1millisecond. The PowerEdge hosts run about 30 virtual machines using VMware vSphere 5.5.
"It's been running now for six months and I haven't had any problems on the read latency," Lane said.
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