Displaying target queue depth statistics
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If you suspect that a target queue depth setting is causing performance issues on your storage array, you should check the value that is set for the queue depth and check the state of requests on the FC initiator ports.
There are different levels of detail that you can access to determine whether there are problems processing requests on target ports. The following steps describe how to determine the current setting for the target port queue depth, determine whether there are requests waiting on the ports, and display detailed port statistics to help you understand the workload on the port.
storage array showcommand with the
-instanceparameter to show the current value of the target port queue depth.
> set advanced > storage array show -instance Name: HP2 Prefix: HP-2 Vendor: HP Model: HSV300 options: Serial Number: 50014380025d1500 Target Port Queue Depth: 512 LUN Queue Depth: 32 Upgrade Pending: false Optimization Policy: eALUA Affinity: aaa Error Text: -
storage array port show -fields max-queue-depthcommand to show the queue depth setting for each port on the storage array.
> set advanced > storage array port show -fields max-queue-depth name wwnn wwpn max-queue-depth --------------- ---------------- ---------------- --------------- EMC_SYMMETRIX_1 50060480000001a0 50060480000001a0 - EMC_SYMMETRIX_1 50060480000001a1 50060480000001a1 - EMC_SYMMETRIX_1 50060480000001b0 50060480000001b0 - EMC_SYMMETRIX_1 50060480000001b1 50060480000001b1 256
A value of "`-` for
Max Queue Depthindicates that the port does not have a specific max queue depth setting and is using the value set at the storage array level.
storage array port showcommand to display performance information about storage array target ports.
The results of this command help you determine whether there are performance problems related to the ports. The
%waitingvalues provide a high-level view of the performance on a port. If these values show a high percentage of requests waiting to be processed or show that the port is busy for a great percentage of time, then you might want to investigate further into the state of the port.
vgv3070f51::*> storage array port show Array Name: HP2 WWNN: 50014380025d1500 WWPN: 50014380025d1508 Connection Type: fabric Switch Port: vgbr300s70:9 Link Speed: 4 GB/s Max Queue Depth: - LUN Link Node Initiator Count IOPS KB/s %busy %waiting Errs --------- --------- ----- ------ ------ ------- ---------- ---- vgv51-02 0a 21 2 53 0 0 0 vgv51-01 0a 21 2 48 1 0 0
You can obtain more detailed information about ports by using the
storage array port show -fieldscommand with the