vSphere vs. Hyper-V

Metron

Performance Showdown

Objectives

• Architecture

• Available metrics

• Challenges in virtual environments

• Test environment and methods

• Results, conclusions, and caveats

vSphere Architecture

Small hypervisor footprint

Hyper-V Architecture

Windows OS required - Larger footprint

vSphere Memory Management Features

Transparent page sharing

Memory borrowing

Memory compression

…and Paging

Hyper-V Memory Management Feature

Dynamic memory for enlightened Windows VMs

Key Performance Metrics

vSphere

CPUAvg. CPU Usage in MHzCPU Ready Time

MemoryAvg. Memory Usage in KBBalloon KBSwap Used KBConsumedActive

I/OQueue LatencyKernel LatencyDevice Latency

Hyper-V

CPUHypervisor Logical Processor % Hypervisor Virtual Processor %

MemoryDynamic Memory BalancerDynamic Memory PressureVM Vid Partition

I/OVirtual Storage DeviceVirtual Network Adapter

Challenges in Virtual Environments

- Clock skew

- NUMA (non-uniform memory access) scheduling

- Pass-through I/O

- Workload definition

- 32 versus 64 bit OS and applications

- Where to use solid state I/O devices

- Storage tiers

- Hidden overhead

- etc...

Test Environment

- AMD Phenom II 3.3 GHz- 8 GB RAM- 1TB Hitachi 7200 RPM HD SATA 2 interface- 1GB Onboard network interface

- vSphere 5- Hyper-V role installed on Windows 2008 R2 SP1

- 2 x Windows 7 SP1 VM with integration services- 2 x CentOS 6.2 VM with integration services v3.2

- Simple custom benchmarks using ActiveState perl v5.14- cpu.pl, disk.pl, mem.pl, net.pl

Testing Methods

Virtual Machineswin_25, win_26centos_11, centos_12

Win7 VMs configured with 512MB min, 64GB max dynamic memory. Centos VMs 2GB.

VMs _25, _12 configured with 2 vCPU

* No Pass-Through

Hyper-V HostnameHyper30

vSphere Hostname192.168.0.99

Individual Tests- CPU w/1 process- CPU w/2 process- Disk on 1vCPU VMs- Mem on 1vCPU VMs- Net on 1vCPU VMs

Combined TestsAll VMs running CPU and Mem. 2 vCPU VMs running Disk and Net.

Each set of testing was run identically on the same host using both hypervisors

Results - Individual VM CPU

Surprisingly Win7 on Hyper-V appears slower

Results - Individual VM CPU

Extra vCPU no help with one process

Results - Individual VM CPU

Twice the work in the same time

Results - Individual VM CPU

Summary of CPU results

- Windows CPU performance on Hyper-V was significantly slower

- Two vCPUs running a single process had little negative impact

Results - Individual VM Disk

Write a 512 MB file

Results - Individual VM Disk

Read the 512 MB file

Results - Individual VM Disk

Abysmal performance for Windows on Hyper-V

Results - Individual VM Disk

Summary of disk I/O results

- Random I/O on a Hyper-V dynamic disk had terrible performance

Results - Individual VM Memory

No penalty for dynamic memory

Results - Individual VM Network

Slight advantage for vSphere

Results - Combined Test

And now… for the grand finale

All workloads running at the same time on multiple VMs

The winner is….

Results - Combined Test

Draw - except disk workload on Hyper-V did not finish

CPU Details - Both platforms on the same chart

Detail CPU Metrics

- vSphere VM ready time

- Hyper-V Guest run time

CPU Details - vSphere CPU Ready Time

CPU Details - Hyper-V Guest Run Time

Detail Memory Metrics

- vSphere memory consumed by VMs- vSphere memory ballooning- vSphere paging

- Hyper-V memory balancer average pressure- Hyper-V memory current pressure- Hyper-V physical page allocation

Memory Details - vSphere Ballooning

Memory Details - vSphere Paging

Memory Details - vSphere Consumed

Memory Details - Hyper-V Memory Balancer Pressure

Memory Details - Hyper-V Memory Current Pressure

Memory Details - Hyper-V Pages Allocated

Detail I/O Metrics

- vSphere queue latency- vSphere device latency

- Hyper-V disk throughput

I/O Details - vSphere Queue Latency

I/O Details - vSphere Device Latency

I/O Details - Hyper-V Disk Throughput

Interesting Observations

- Hyper-V dynamic memory- Hyper-V dynamic disk device performance

Dynamic Memory in action - High Pressure

Dynamic Memory in action - Low Pressure

Hyper-V - Random I/O on Dynamic Disks

Chart from Hyper-V MSDN Blog by: Tony Voellm

Conclusions, Caveats, and Final Thoughts

Overall the combined results were surprising close

Individual tests produced some interesting findings

- Windows CPU performance on Hyper-V was significantly slower- Two vCPUs running a single process had little negative impact- Random I/O on a Hyper-V dynamic disk had terrible performance- Hyper-V dynamic memory worked great with no performance penalty

Caveats

- Workloads were very general and dependent on perl implementation- Many more variables could be taken into account- Result may be different on other hardware

Running benchmarks in your own environment should bedone to help make the best informed decisions.

Thank you for attending

Charles Johnson

Metron-Athene Inc.

Charles@metron-athene.com

vSphere vs. Hyper-V