124 IBM TotalStorage DS6000 Series: Performance Monitoring and Tuning
Total I/O requests (requested I/O operations per second)
You may only enable a particular threshold once minimum values for warning and error levels
have been defined. If you attempt to select a threshold and enable it without first modifying
this value, you will see a notification like Figure 4-34.
Figure 4-34 DS8000/DS6000 Threshold enable warning
To modify the warning and error values for a given threshold, you may select the threshold,
and click the Properties button. The panel in Figure 4-35 will be shown. You can modify the
threshold as appropriate, and accept the new values by selecting the OK.
Figure 4-35 Modifying DS8000/DS6000 threshold warning and error values
4.3.5 Exploiting gauges
Gauges are a very useful tool and help in identifying performance bottlenecks. In this section
we will show the drill down capabilities of gauges. The purpose of this section is not to cover
performance analysis in detail for a specific product, but to highlight capabilities of the tool.
You may adopt and use a similar approach for the performance analysis.
Before exploiting gauges, appropriate time frame samples which cover high/low I/O rate
should be collected.
Tip: In TotalStorage Productivity Center for Disk, default thresholds warning and error
values of -1.0 are indicators that there is no recommended minimum value for the
threshold and are therefore entirely user defined. You may elect to provide any reasonable
value for these thresholds, keeping in mind the workload in your environment.