6.7

Table Of Contents
You can also set advanced options to further configure the aggressiveness level of Storage DRS.
Space utilization
difference
This threshold ensures that there is some minimum difference between the
space utilization of the source and the destination. For example, if the
space used on datastore A is 82% and datastore B is 79%, the difference is
3. If the threshold is 5, Storage DRS will not make migration
recommendations from datastore A to datastore B.
I/O load balancing
invocation interval
After this interval, Storage DRS runs to balance I/O load.
I/O imbalance threshold Lowering this value makes I/O load balancing less aggressive. Storage
DRS computes an I/O fairness metric between 0 and 1, which 1 being the
fairest distribution. I/O load balancing runs only if the computed metric is
less than 1 - (I/O imbalance threshold / 100).
Set Storage DRS Runtime Rules
Set Storage DRS triggers and configure advanced options for the datastore cluster.
Procedure
1 (Optional) Select or deselect the Enable I/O metric for SDRS recommendations check box to
enable or disable I/O metric inclusion.
When you disable this option, vCenter Server does not consider I/O metrics when making Storage
DRS recommendations. When you disable this option, you disable the following elements of Storage
DRS:
n
I/O load balancing among datastores within a datastore cluster.
n
Initial placement for virtual disks based on I/O workload. Initial placement is based on space only.
2 (Optional) Set Storage DRS thresholds.
You set the aggressiveness level of Storage DRS by specifying thresholds for used space and I/O
latency.
n
Use the Utilized Space slider to indicate the maximum percentage of consumed space allowed
before Storage DRS is triggered. Storage DRS makes recommendations and performs migrations
when space use on the datastores is higher than the threshold.
n
Use the I/O Latency slider to indicate the maximum I/O latency allowed before Storage DRS is
triggered. Storage DRS makes recommendations and performs migrations when latency is higher
than the threshold.
Note The Storage DRS I/O Latency threshold for the datastore cluster should be lower than or
equal to the Storage I/O Control congestion threshold.
vSphere Resource Management
VMware, Inc. 106