SQL Server Performance Scalability With VMware vCloud Air
vSphere can very easily handle executing Microsoft SQL Server on four-socket servers with huge numbers of cores—with vSphere 5.5 on Westmere-EX and with vSphere 6 on Ivy Bridge-EX. We recently ran the same kind of tests on vCloud Air to gauge how these enterprise databases with sensitive and mission critical performance requirements perform over a cloud environment.
The tests depict that SQL Server databases scale extremely well on vCloud Air with a various kind of virtual machine (VM) counts and virtual CPU (vCPU) sizes.
The benchmark tests were executed with vCloud Air utilizing their Virtual Private Cloud (VPC) subscription-based service. This is extremely compelling hybrid cloud service which permits for an on-premises vSphere infrastructure to be extended into the public cloud in a protected, secure and scalable way.
The underlying host hardware is inclusive of two 8-core CPUs for a total of 16 physical cores, that implies that the maximum number of vCPUs was 16 (though additional processors were present via Hyper-Threading, they were not used).
Windows Server 2012 R2 used to be the guest OS, and SQL Server 2012 Standard version was the database engine utilized for all the VMs. All databases were placed or located on an SSD Accelerated storage tier to achieve maximum disk I/O performance. The test configurations are displayed below:
An open-source OLTP database stress tool namely, DVD Store 2.1 was the workload utilized to stress the VMs. The prime experiment was to extend to scale up the number of 4 vCPU VMs.
The graph depicted below shows that as the total number of VMs is increased from 1 to 4, then the aggregate performance (measured in terms of ‘orders per minute’, or OPM) increases, overall elevating the performance correspondingly.
While the size of every VM was doubled from 4 to 8 virtual CPUs, the OPM (measured in terms of ‘orders per minute’, or OPM) also around doubles for the same number of VMs as depicted in the chart shown below:
This final chart consists of a test run with single large 16 vCPU VM. As assumed, the 16 vCPU performance was very similar to the four 4vCPU VMs and the eight 2vCPU VM test cases. The little drop can be attributed to spanning several physical processors and therefore multiple NUMA nodes within a one VM.
In brief, SQL Server was observed to perform and scale optimally well running over the vCloud Air with 4, 8, and 16 vCPU VMs. In the future, expect for more such benchmarks over the cloud as it continues to evolve!