HP 3PAR StoreServ 7450 4-node HP 3PAR Command Line Interface Administrator& - Page 164

Reporting

Page 164 highlights

when a queue-full message arrives at the ESXi host. This reduction in the queue length gives the array an opportunity to decrease the number of outstanding I/Os at its end. In vSphere 5.1 U1, AQD can be configured by LUN, or globally for the ESXi host. Combining QoS rules with SIOC and ADQ provides I/O congestion control on three different levels: the workload will honor the QoS limits, and it will be impacted indirectly when SIOC reacts to latency increases and when AQD responds to queue-full messages from QoS rules. Coordination and some experimenting may be necessary to deliver the best results. VMware Storage DRS, a new feature introduced in VMware vSphere 5.0, groups datastores into a cluster so that they are managed as a single unit. This allows for load balancing VMs across datastores based on I/O latency and space utilization in an automated or manual way. Storage DRS leans on Storage vMotion for migrating VMDKs to different datastores. Combining HP 3PAR Priority Optimization with Storage DRS requires careful planning of the QoS rules. A QoS rule governs one or more LUNs that make up a datastore. Storage DRS implies a source and a destination datastore, each possibly subject to a QoS rule. The QoS rule if any on the Storage DRS destination datastore should have enough headroom to accommodate the additional I/O capacity of the migrated VMDK. If the workload's I/O characteristics are not very well known, HP recommends manual Storage DRS migrations over automated ones to detect any I/O congestion due to the migration in an early stage. Reporting Continuous performance monitoring of all critical parameters of a storage system is essential in managing a storage system. HP 3PAR Priority Optimization features new charts in the HP 3PAR MC for monitoring QoS rules graphically over time. For example, Figure 19 (page 164) shows a graph of the behavior for a number of VVsets with their respective QoS rule and the all_others rule over a period of time. Figure 19 Historic Behavior of QoS Rules on System Use the HP 3PAR CLI command statqos to display run-time statistics of active QoS rules in columns. The command produces output every 2 seconds; this interval can be changed. Depending on the active QoS rule, values for the following parameters are displayed: • IOPS • Bandwidth 164 HP Priority Optimization

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when a queue-full message arrives at the ESXi host. This reduction in the queue length gives the
array an opportunity to decrease the number of outstanding I/Os at its end. In vSphere 5.1 U1,
AQD can be configured by LUN, or globally for the ESXi host.
Combining QoS rules with SIOC and ADQ provides I/O congestion control on three different
levels: the workload will honor the QoS limits, and it will be impacted indirectly when SIOC reacts
to latency increases and when AQD responds to queue-full messages from QoS rules. Coordination
and some experimenting may be necessary to deliver the best results.
VMware Storage DRS, a new feature introduced in VMware vSphere 5.0, groups datastores into
a cluster so that they are managed as a single unit. This allows for load balancing VMs across
datastores based on I/O latency and space utilization in an automated or manual way. Storage
DRS leans on Storage vMotion for migrating VMDKs to different datastores. Combining HP 3PAR
Priority Optimization with Storage DRS requires careful planning of the QoS rules. A QoS rule
governs one or more LUNs that make up a datastore. Storage DRS implies a source and a
destination datastore, each possibly subject to a QoS rule. The QoS rule if any on the Storage
DRS destination datastore should have enough headroom to accommodate the additional I/O
capacity of the migrated VMDK. If the workload’s I/O characteristics are not very well known, HP
recommends manual Storage DRS migrations over automated ones to detect any I/O congestion
due to the migration in an early stage.
Reporting
Continuous performance monitoring of all critical parameters of a storage system is essential in
managing a storage system. HP 3PAR Priority Optimization features new charts in the HP 3PAR
MC for monitoring QoS rules graphically over time. For example,
Figure 19 (page 164)
shows a
graph of the behavior for a number of VVsets with their respective QoS rule and the
all_others
rule over a period of time.
Figure 19 Historic Behavior of QoS Rules on System
Use the HP 3PAR CLI command
statqos
to display run-time statistics of active QoS rules in
columns. The command produces output every 2 seconds; this interval can be changed. Depending
on the active QoS rule, values for the following parameters are displayed:
IOPS
Bandwidth
164
HP Priority Optimization