Say there are 5 VMs each with 2,000 MB memory allocated. Two (2) of these VMs have their share values set to “normal” while 3 VMs have share value set to “high”. The ESX host only has 4,000 MB of physical machine memory available for virtual machines. Determine the number of shares and the amount of physical memory that will be assigned to each VM based on these share values.

Example: Say there are 5 VMs each with 2,000MB memory allocated and their share values set to “normal”. The ESX host only has 4,000MB of physical machine memory available for virtual machines. Each VM receives 20,000 shares according to the “normal” setting (10 * 2,000). The sum of all shares is 5 * 20,000 = 100,000. Every VM will receive an equal share of 20,000/100,000 = 1/5th of the resources available = 4,000/5 = 800MB.

Now say the shares setting on 1 VM is changed to “High”, which results in this VM receiving 40,000 shares (20 * 2,000) instead of 20,000. The sum of all shares is now increased to 120,000. This VM will receive 40,000/120,000 = 1/3rd of the resources available. Thus 4,000/3 = 1333 MB. All the other 4 VMs will receive only 20,000/120,000 = 1/6th of the available resources = 4,000/6 = 666 MB each.