Many Monitor Viewer windows and Historical Server views cause Monitor Server to create summaries of monitoring events.
The scan interval specifies how often Monitor Server obtains new information from Adaptive Server event buffers. The scan interval at start-up is an initial scan interval. During execution, if Monitor Server detects that event loss has occurred or is about to occur, it reduces the scan interval in an attempt to prevent losses. For the remainder of execution, the scan interval remains at the reduced level.
You can view the current value of scan_interval with the sms_status scan_interval command. See sms_status for more information about this command.
By default, Monitor Server computes an initial scan interval at start-up. The calculation is based on the event buffers per engine Adaptive Server configuration parameter. You can override the computed value for the initial scan interval with the Monitor Server scan_interval configuration parameter.
Overriding the default computation for initial scan interval is generally not necessary. If you notice that the scan interval tends to reduce over time, a more effective method of ensuring that Monitor Server does not lose events is to increase the event buffers per engine Adaptive Server configuration parameter. Increasing the number of event buffers makes Monitor Server scan less frequently. See “Configuring event buffers” for more information.
The configuration file entry for this parameter is:
where the value is specified in milliseconds. The minimum valid scan interval is 1 millisecond. The default is calculated by Monitor Server and is generally sufficient.