Unified Manager collects and analyzes workload activity every 5 minutes to identify performance events, and it detects configuration changes every 15 minutes. It retains a maximum of 30 days of 5-minute historical performance and event data, and it uses this data to forecast the expected range for all monitored workloads.
Unified Manager must collect a minimum of 3 days of workload activity before it can begin its analysis and before the expected range for I/O response time and operations can be displayed on the Performance/Volume Details page and in the Event details page. While this activity is being collected, the expected range does not display all changes occurring from workload activity. After collecting 3 days of activity, Unified Manager adjusts the expected range, every 24 hours at 12:00 a.m., to reflect workload activity changes and establish a more accurate performance threshold.
During the first 4 days that Unified Manager is monitoring a volume, if more than 24 hours have passed since the last data collection, the charts on the Performance/Volume Details page will not display the expected range for that volume. Events detected prior to the last collection are still available.