PEGA0074 alert: Decision Data Store write time above threshold
The PEGA0074 alert is triggered when the Decision Data Store service write time exceeds its threshold for a record.
Example message text
DDS write duration <actual value> ms exceeds the threshold of <threshold> ms for column family <column family> with keys <keys> record size <record size> KB
The following variables are in the message text:
- <threshold> is the maximum time for the Decision Data Store write activity. The default value is 50 ms. The threshold value is set in the alerts/ddsWriteTimeThreshold Dynamic System Settings.
- <actual value> is the amount of time that the Decision Data Store service needed to write the record.
- <column family> is the name of the column family that is the Cassandra table where the record is stored. The column contains the data set name where the record was written.
- <keys> are the data set keys that were specified during data set creation. The combination of the column family and the keys uniquely identifies the record that triggered the alert.
Reasons for the alert
To eliminate this alert, check the size of the record that was written. If the size is large (approaching 1MB), consider modifying the application to reduce the record size. For example, determine whether all fields are required to be stored and eliminate any that are not needed, eliminate duplicate data, and analyze the data flow and consider removing any aggregations of a large amount of data into a single record. Writing of large-size data can cause high latencies. Therefore, check the processor usage, disk latency, and the latency of the network between the Decision Data Store nodes. If the latency is high, add more nodes to the cluster. For more information, see Configuring the Decision Data Store service.