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 vSphere Hypervisor 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
- Virtualization-Aware Networking and Security Solutions
- Industry Recognition
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.
You’ll see that VMware vSphere 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. Blog discussions include:
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 vSphere Hypervisor can support more virtual machines on the same hardware than Hyper-V and Citrix XenServer and Red Hat Enterprise Virtualization. Of all x86 bare-metal hypervisors, VMware vSphere supports the broadest set of memory overcommit technologies 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 vSphere host, transparent page sharing alone can typically save anywhere from 5 to 30 percent of the server’s total memory by consolidating identical memory pages (as high as 45% memory savings in a VDI environment). VMware’s balloon driver can also reclaim idle memory so other virtual machines can make use of it. Last, memory compression, improves the performance of virtual machines when memory is under contention, because less virtual memory is swapped to disk as a result.
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
After dismissing the value of these VMware memory management techniques for quite some time, both Citrix and Microsoft have turned around and released advanced memory capabilities of their own. But in both cases, they still fall far short of the full breadth of what VMware delivers. For instance, Citrix’s dynamic memory in XenServer 5.6 and newer cannot dynamically adjust the size of its balloon driver based on real-time VM usage. This limitation can create major performance issues for active virtual machines while leaving lots of unused RAM in idle virtual machines.