Disk shares "Proportional share" method. If multiple VMs access the same VMFS datastore and the same logical unit number (LUN), there may be contention as they try to access the same virtual disk resource at the same time. Under certain conditions, the administrator may need to prioritize disk access for specific virtual machines; this can be done using disk shares . If you want to give priority to specific VMs when there is access contention, you can do so using disk shares. Using disk shares, the administrator can ensure that the more important virtual machines get preference over less important virtual machines for I/O bandwidth allocation. “Shares is a value that represents the relative metric for controlling disk bandwidth to all virtual machines. The values are compared to the sum of all shares of all virtual machines on the server.” “Disk shares are relevant only within a given host. The shares assigned to virtual machines on one host have no eff