Allocate storage I/O resources to virtual machines based on importance by assigning a relative amount of shares to the virtual machine.
Unless virtual machine workloads are very similar, shares do not necessarily dictate allocation in terms of I/O operations or megabytes per second. Higher shares allow a virtual machine to keep more concurrent I/O operations pending at the storage device or datastore compared to a virtual machine with lower shares. Two virtual machines might experience different throughput based on their workloads.
Prerequisites
Launch the vSphere Client and log in to a vCenter Server system.
Procedure
- Select a virtual machine in the vSphere Client inventory.
- Click the Summary tab and click Edit Settings.
- Click the Resources tab and select Disk.
- Select a virtual hard disk from the list.
- Click the Shares column to select the relative amount of shares to allocate to the virtual machine (Low, Normal, or High).
You can select
Custom to enter a user-defined shares value.
- Click the Limit - IOPS column and enter the upper limit of storage resources to allocate to the virtual machine.
IOPS are the number of I/O operations per second. By default, IOPS are unlimited. You select Low (500), Normal (1000), or High (2000), or you can select Custom to enter a user-defined number of shares.
- Click OK.
Results
Shares and limits are reflected on the
Resource Allocation tab for the host and cluster.