Understanding Polling and Metric Collection
The first poll after starting the integration instance is used to prime the delta cache and is not stored in the database. After the initial poll, collected statistics are loaded into the IO database.
SVC Integration polling always starts on the minute, never on a partial minute and the start times are directly associated with the polling interval set in IBM SVC. For example, if you set SVC statistics frequency collection interval to 5 minutes, metric collection on IO would start on a rounded minute and occurs every 5 minutes after that, such as 1:25:00, 1:30:00, 1:35:00, etc. Collection never occurs in between interval settings or at increments less than a minute, such as 1:26:14.
However, the IBM SVC statistics files can be generated at any time during the configured interval. Collected statistics are loaded into the IO database and associated with the date and time the statistics file was generated by the IBM SVC. This means that the database timestamp will not align to the SVC Integration polling time.
As an example, if SVC started a statistics collection at 1:21:33 AM PST with a 5 minute interval, the next poll performed by the SVC Integration would be 1:25:00. The integration would pull the data from the SVC file generated at 1:21:33 and load it into the IO database with that timestamp.
When you view the SVC Integration information in IO, you can see the last time that metrics collection completed. The completion time is the polling start time plus the length of time it took to finish the metrics collection. Continuing with the previous example, if polling started a 1:25:00 AM PST and took 3 minutes and 19 seconds, the Last Metrics Collection time would display 1:28:19 AM PST. However the latest data showing in the database would be at 1:21:33 AM, which is the timestamp from IBM SVC.
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