A new whitepaper detailing high performance SQL workloads running in Hyper-V R2 virtual machines.  The paper can be downloaded here...  Below are a few highlights/examples from the paper.

Dedicated Passthough LUN’s vs VHD’s

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Figure 3: I/O and disk latency for dedicated pass-through disks versus VHDs

Multi-Instance Throughput: Native versus Virtual (16 core server)

The results of this test are summarized as follows:

  • Slightly higher logical processor utilization is required to achieve the same throughput with virtualization due to minimal additional processor overhead.
  • Native instances and virtual instances achieve the same level of scalability.
  • I/O performance of ~5 percent for pass-through disks is greater than fixed-size VHDs as shown in Figure 3. Note that pass-through disks have an approximately one millisecond lower latency as compared to fixed-size VHDs.
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Figure 4: Multi-Instance throughput: native instances versus virtual instances (16 cores)

Taylor Brown
Hyper-V Enterprise Deployment Team
taylorb@microsoft.com
http://blogs.msdn.com/taylorb

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