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Table Of Contents
If snapshot files are consuming high datastore space, consider consolidating them to the virtual disk when
they are no longer needed. Consolidating the snapshots deletes the redo log files and removes the
snapshots from the vSphere Web Client user interface. For information about consolidating the data
center, see the vSphere documentation.
Storage I/O Control Normalized Latency
This chart displays the normalized latency in microseconds on the datastore. Storage I/O Control
monitors latency to detect congestion on the datastore. This metric computes a weighted response time
across all hosts and VMs accessing the datastore. I/O count is used as the weight for the response time.
It captures the device level latency and does not include any queuing inside the hypervisor storage stack
or inside the VM. It is adjusted for the I/O size. High latencies that are the result of large I/Os are
discounted so as not to make the datastore seem slower than it really is. Data for all virtual machines is
combined. This chart displays zero values when Storage I/O Control is disabled.
This chart is located in the Performance view of the datastore Performance tab. The
sizeNormalizedDatastoreLatency counter can also be displayed for datastore cluster charts.
Table 132. Data Counters
Chart Label Description
Storage I/O Control
Normalized Latency
Storage I/O Control monitors latency to detect congestion on the datastore.
n
Counter: sizeNormalizedDatastoreLatency
n
Stats Type: Absolute
n
Unit: Microseconds
n
Rollup Type: Average
n
Collection Level: 3
Storage I/O Control Aggregate IOPs
This chart displays the number of I/O operations per one second on the datastore, aggregated across all
hosts, and virtual machines accessing this datastore. The chart displays zero values when Storage I/O
Control is disabled.
This chart is located in the Performance view of the datastore or the datastore cluster Performance tab.
The counter can be displayed for datastore and datastore cluster charts.
Table 133. Data Counters
Chart Label Description
Storage I/O Control Aggregate IOPs Number of I/O operations per second on the datastore, aggregated across all hosts, and
virtual machines accessing the datastore.
n
Counter: datastoreIops
n
Stats Type: Absolute
n
Unit: Number
n
Rollup Type: Average
n
Collection Level: 3
vSphere Monitoring and Performance
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