Settings disk shares on virtual machine disks

Every ESXi host runs a local scheduler to monitor and balance the I/O between the virtual machines. If there are virtual machines generating a considerable amount of I/O (more than normal), then it is important to make sure that the other virtual machines running on the same datastore remain unaffected, in a manner that they should be allowed to issue I/O to the device with performance expected. This can be achieved by setting per-disk (vmdk) shares thereby controlling the volume of I/O each participating virtual machines can generate, during contention. Disk shares works pretty much like the CPU or memory shares and would only kick-in during contention. The default virtual disk share value is 1,000, high being 2,000 and low being 500. The disk with a relatively higher share value will get to issue a larger volume of I/O to the device...