On Tuesday, October 6, QCT opened its Cloud Solution Center located within QCT’s new U.S. corporate headquarters in San Jose. The new facility is designed to test and demonstrate modern cloud datacenter solutions that have been jointly developed by QCT and it’s technology partners. Among the demonstrated solutions, there was an innovative VDI deployment that has been jointly developed by QCT and Mellanox and based on a virtualized hyper-converged infrastructure with scale-out Software-Defined-Storage and connected over 40GbE.
VDI enables companies to centralize all of their desktop services over a virtualized data center. With VDI, users are not tied to a specific PC and can access their desktop and run applications from anywhere. VDI also helps IT administrators by creating more efficient and secure environments, which enables them to better serve their customers’ business needs.
VDI efficiency is measured by the number of virtual desktops that a specific infrastructure can support, or, in other words, by measuring the cost per user. The major limiting factor is the access time to storage. Replacing the traditional Storage Area Network (SAN) architecture with a modern scale-out software-defined storage architecture with fast interconnect supporting 40GbE significantly eliminates potential bottlenecks, enabling the lowest total cost of ownership (TCO) and highest efficiency.
The solution includes a cluster with eight servers (based on QCT’s 4-node server, model T41S-2U QuantaPlex) with dual Intel Xeon E5-2690 V3 2.6GHz processors and 256GB of memory. Each server included six 800GB SSDs, one of which was dedicated to the OS. Out of the eight servers, two were dedicated to management, which runs over 10GbE.
Another two servers were used as pure storage nodes (in addition to the local SSDs that are on the computer servers. This is to compensate for the SSDs wasted on installed ESXi OS in the four-node scale-out Software Defined Storage cluster). The network is based on Mellanox’s end-to-end 40GbE interconnect solution, including the SX6036 36-port 40GbE switch, dual-port ConnectX-3 40GbE NICs (one 40GbE NIC for the storage cluster and one 10GbE NIC for management), and Mellanox’s LinkX copper interconnect cables.
On the software side, ESXi 5.5U2 build 2068190 and Horizon View 5.3.4 build 2581701 were used. Within the desktop sessions, the Windows 7 64-bit operating system was used. Each persistent desktop used 2GB of memory and one vCPU.
Figure 1: Interconnect configuration of the VDI cluster
VDI performance was measured using Login VSI’s VDI load generator, the industry standard load testing solution for virtualized desktop environments. The tool creates the actual workload of a typical Windows user using Microsoft Office applications. The following chart shows 500 virtual desktop sessions running in parallel, during which Login VSI’s response times were below 1.2 seconds. Deploying 500 VMs took 59 minutes, and booting all the sessions was accomplished in only 3 minutes.
Figure 2: Login VSI benchmark results
Designing an efficient VDI solution has traditionally been a complicated task that often led to bottlenecks in the pure storage performance, and in many cases required using very expensive flash-based systems that resulted in lower-than-expected efficiency gains. Using the solutions in QCT’s Cloud Solution Center that is based on scale-out software-defined storage connected by the Mellanox end-to-end 40GbE solution guarantees a hassle-free and most efficient VDI deployment.