– Enable/Disable Storage I/O Control
Enable Storage I/O Control in the vSphere Resource Management Guide on page 49.
Storage I/O Control (SIOC) extends the constructs of shares and limits to handle storage I/O resources.
Steps to enable SIOC:
Enable Storage I/O Control for the datastore.
Set the number of storage I/O shares and upper limit of I/O operations per second (IOPS) allowed for
each virtual machine.
By default all virtual machines are set to Normal (1000) shares with unlimited IOPS.
Datastores that are Storage I/O Control-enabled must be managed by a single vCenter Server system.
SIOC is supported on Fibre Channel-connected, iSCSI-connected, and NFS-connected storage. Raw Device Mapping (RDM) is not supported.
SIOC is not supported for datastores with multiple extents.
Before using SIOC on datastores that are backed by arrays with automated storage tiering capabilities, check the VMware Storage/SAN Compatibility Guide to verify whether the automated tiered storage array has been certified to be compatible with SIOC.
SIOC will not function correctly if you share the same spindles on two different datastores.
Configure SIOC for a datastore:
The congestion threshold value for a datastore is the upper limit of latency that is allowed for a datastore before SIOC assign importance to the virtual machine workloads based on their allocated shares.
Setting SIOC Shares and IOPS Limit on a Virtual Machine Disk
Allocate storage I/O resources to virtual machines based on importance by assigning a relative amount of shares to the virtual machine.
