ALR0501W The Disk Utilization Percentage of array array name in storage system storage system name was measured to be measured value%. This violated the warning-stress boundary value of boundary value%.
Explanation
Disk Utilization Percentage measures the approximate utilization percentage of the arrays in monitored storage systems. This value represents the average percent of time that the disks associated with the array were busy. A threshold was defined on this metric, which causes the measured value to be compared to the defined boundaries for each set of performance statistics collected from the storage system.
This message indicates that a threshold boundary violation occurred. In this case, the specified array in the storage system has a Disk Utilization Percentage value that is greater than or equal to the warning-stress boundary, but less than the critical-stress boundary that was defined for the related threshold.
Action
The threshold violation might indicate that a performance problem exists for this array. Either the array is experiencing a hardware or software related problem that is causing a drop in performance, or the array is being overloaded with too high a workload. If the workload is too high, moving some of the array's workload to other less busy arrays might resolve the problem.
However this threshold indication is only as good as its defined boundary values. If the specified boundary value is too low, IBM Spectrum Control might recognize many violations, even though there is really no underlying performance problem with the array. In this case, increase the boundary value in the threshold definition to reduce the number of unnecessary alerts.
Note that some highly sequential workloads such as batch or backup processing might continually exceed the threshold because they drive the arrays to high utilization percentages. For these types of workloads, a high utilization indicates that the work is being performed very efficiently and is not a cause for concern. If this situation occurs for your workload, consider enabling the Sequential I/O Percentage filter. Use this filter to ignore any violations of the Disk Utilization Percentage threshold for highly-sequential workloads.