A Data Collector (DC) is raising Events in DX NetOps Performance Management about it's performance.
A sample message from the system generated Event states:
Data Collector <DC_HostName>:<DCM_ID> dropped 1 of 1 scheduled poll requests for Metric Family NormalizedDataCollectorSystemStatisticsInfo, Vendor Cert DAHealthDataCollectorPollingStatistics for Poll Rate 60000. The Data Collector may be overloaded or the system time has changed.
It is seen for different Metric Families and/or Vendor Certification combinations.
The Data Collector may be overloaded or the system time has changed.
All supported Performance Management releases
In this scenario the Data Collector is under resourced. It did become overloaded due to lack of resources.
Configure the Data Collector so that it meet the minimum resource requirements according to the DX NetOps Performance Management Sizing tool.
Taking that step resolved the problem.
If the systems resources are sufficient ensure the Data Aggregator and Data Collector are in time sync with each other.
The Data Collector and Data Aggregator must be in sync with each other for time.
If these are no longer in sync these Events would be triggered. See Knowledge Base article titled "Polls dropped due to time shift on data collector." for more information.