VMware

Avoid unnecessary risk and overhead by choosing a robust and production-proven hypervisor as the foundation for your virtualized datacenter.  Selecting the right hypervisor is the first step towards success in building a virtual infrastructure.

 

Not all hypervisors are equal. Learn more about how VMware ESX/ESXi is — and will continue to be — the industry’s most robust and production-proven hypervisor and why VMware is the best choice for building a virtual infrastructure.

  • Comparing Hypervisors
  • Hyper-V and Xen Architectures: Too much code
  • Achieve Scalable Performance
  • Why File Systems Matter
  • An Ecosystem of Virtualization Security Solutions
  • Industry Recognition

Questions? 1-877-486-9273

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Achieve Better Scalability and Performance in your Data Center

The hypervisor plays a key part in delivering scalable virtualization performance. See detailed performance demonstrations and comparisons in the performance section of the VMware website.

Watch a technical video on the VMware Performance Advancements in VMware vSphere.

You’ll see that VMware ESX/ESXi achieves high-performance throughput in a heavily virtualized environment, even as the number of total supported users and virtual machines per physical host increases. Join the discussion on the latest performance topics on VROOM!—VMware’s performance team blog. Recent blog discussions include:

How fast can ESX go? 100,000 IOPS and more!

I/O is one of the most critical performance bottlenecks in virtual environments, but even the most I/O-intense application runs fast on VMware ESX. The result is that end users have no idea that their applications are being served from a virtual environment—any latency or overhead is usually imperceptible to the end-user. A recent test conducted by VMware with the EMC Midrange Partner Solution Engineering Team, showed that a single ESX host is capable of driving over 100,000 IOPS, maxing out the throughput of 500 disk drives in a SAN. To put this into perspective, you would need to run 200,000 Microsoft Exchange mailboxes (LoadGen heavy user profile) to generate an I/O rate of 100,000 IOPS. With that kind of performance power available, even your most demanding workloads can be virtualized.

Other vendors have tried to show-off their I/O performance, but their test results have been criticized due to suspect test configurations not based on real world virtualization scenarios. They also unrealistically limit tests to only one or two VMs to avoid exposing their scaling weaknesses.

Why does ESX scale and perform so much better than other vendors’ offerings? The reasons are articulated in a recent VMware article, “A Look at Some VMware Infrastructure Architectural Advantages.” Two main reasons are the 1) VMware ESX direct driver model and 2) its more effective management of memory.

Advantages of the ESX Direct Driver Architecture for Performance

The VMware ESX direct driver model utilizes certified and hardened I/O drivers in the VMware ESX hypervisor. These drivers must pass rigorous testing and optimization steps performed jointly by VMware and the hardware vendors before they are certified for use with VMware ESX. With the drivers in the hypervisor, VMware ESX can give them CPU scheduling and memory resources they need to process I/O loads from multiple virtual machines. The Xen and Microsoft architectures rely on routing all virtual machine I/O to generic drivers installed in the Linux or Windows OS in the hypervisor’s management partition. These generic drivers can be overtaxed by the activity of multiple virtual machines – exactly the situation a true bare-metal hypervisor, such as ESXi, can avoid. Windows Server 2008 R2 with Hyper-V and Xen-based products both use generic drivers that are not optimized for many virtual machine workloads.

VMware investigated the indirect driver model, now used by Xen and Hyper-V, in early versions of VMware ESX and quickly found that the direct driver model provides much better scalability and performance as the number of virtual machines on a host increases.

Better Memory Management for Scalability

In most virtualization scenarios, system memory is the limiting factor controlling the number of virtual machines that can be consolidated onto a single server. By more intelligently managing virtual machine memory use, VMware ESX can support more virtual machines on the same hardware than any other x86 hypervisor. Of all x86 bare-metal hypervisors, only VMware ESX supports memory overcommit, which allows the total memory allocated to virtual machines to exceed the physical memory installed on the host. VMware ESX supports memory overcommit with minimal performance impact by combining several exclusive technologies.

Content-based transparent memory page sharing conserves memory across virtual machines with similar guest OSs by seeking out memory pages that are identical across the multiple virtual machines and consolidating them so they are stored only once and shared across multiple machines. Think of it as de-duplication for memory. Depending on the similarity of OSs and workloads running on a VMware ESX host, transparent page sharing alone can typically save anywhere from 5 to 30 percent of the server’s total memory.

If all virtual machines on a host spike at the same time and require all of their memory allocation, VMware DRS can automatically load balance by performing VMotion live migrations of virtual machines to other hosts in the DRS cluster.

Watch a technical video on: VMware Distributed Resource Scheduler and VMware vSphere

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