6.7

3 Click the Virtual Hardware tab and select a virtual hard disk from the list. Expand Hard disk.
4 Select a VM storage policy from the drop-down menu.
If you select a storage policy, do not manually configure Shares and Limit - IOPS.
5 Under Shares, click the drop-down menu and 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.
6 Under Limit - IOPS, click the drop-down menu 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.
7 Click OK.
Enable Storage I/O Control
When you enable Storage I/O Control, ESXi monitors datastore latency and throttles the I/O load if the
datastore average latency exceeds the threshold.
Procedure
1 Browse to the datastore in the vSphere Client.
2 Click the Configure tab.
3 Click Settings and click General.
4 Click Edit for Datastore Capabilities.
5 Select the Enable Storage I/O Control check box.
6 Click OK.
Under Datastore Capabilities, Storage I/O Control is enabled for the datastore.
Set Storage I/O Control Threshold Value
The congestion threshold value for a datastore is the upper limit of latency that is allowed for a datastore
before Storage I/O Control begins to assign importance to the virtual machine workloads according to
their shares.
You do not need to adjust the threshold setting in most environments.
Caution Storage I/O Control might not function correctly if you share the same spindles on two different
datastores.
vSphere Resource Management
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