DIFFERENCE BETWEEN VMWARE SERVER & ESX

DIFFERENCE BETWEEN VMWARE SERVER & ESX

VMWare server can run any virtual machine created by VMWare GSX or ESX or VMWare workstation

More information (official information) is available here

Potential Issue With Cpu Affinity:

§ For SMP VMs, ESX server automatically performs load balancing.

§ Affinity can interfere with ESX server’s ability to meet reservations, shares assigned for VMs.

§ When you move VMs from one host to another affinity might not be applicable

Check if hyperthreading is enabled on ESX host

In the vi client click host ->Configuration ->Processor ->Properties.You will dialog box, with checkbox informing if HT is enabled or not.

For changes to be effective you will have to restart ESX host.

Virtual Machine Manager is responsible for virtualization of CPU.

All modern OS provides support for Virtual Memory, allowing software to use more memory than the physical one. The virtual memory space is divided into blocks, also typically 4KB, called pages. When physical memory is full data for virtual pages that is not present in physical memory is stored on disks.

 

Virtualization overhead

 

 

There is full list of Virtualization overhead in resource management guide.

To fully isolate resource pool, use resource pool type fixed and use reservation & limits.

Group virtual machines for a multi-tier service in a resource pool, Resource pool allow ESX host to assign resources to the service as a whole.

To optimize VMs, disable use of COM ports, LPT ports, Floppy drives,CD-ROMs, USB Adapters, and so on. Those devices are periodically pull by guest OS, even if they are not in use.