When nodes expire, by default they are no longer selectable, nor are they shown, in Monitor displays. However, under certain circumstances it might be beneficial to display them, and control how long expired nodes are shown in Monitor displays. There are three possible modes you can configure for expired nodes:
Mode 1: Expired nodes are not shown in displays (the default)
Mode 2: Expired nodes are shown and selectable in displays indefinitely. Expired nodes persist as expired nodes until they rejoin the cluster. If there is a large population of expired nodes, consider Mode 3.
Mode 3: Expired nodes are shown and selectable in displays for a specified time, then they are removed from displays at a user-specified time. This option enables you to manage the clutter of expired nodes – with the time window with which you wish to investigate them.
NOTE: Expired nodes that rejoin the cluster are no longer considered expired, and thus are displayed and selectable.
To change the node expiration mode you configure three substitutions, ocmRowExpirationMode, ocmRowExpirationTime and ocmRowExpirationTimeForDelete.
Example Mode 1: Expired nodes not shown in displays
sl.rtview.sub=$ocmRowExpirationMode:3
sl.rtview.sub=$ocmRowExpirationTime:25
sl.rtview.sub=$ocmRowExpirationTimeForDelete:25
Where:
$ocmRowExpirationTime is 2.5 times the jmxsampleperiod in seconds
$ocmRowExpirationTimeForDelete is the same value as ocmRowExpirationTime (nodes are deleted as they expire and are thus not displayed)
Example Mode 2: Expired nodes shown and selectable in displays indefinitely
sl.rtview.sub=$ocmRowExpirationMode:1
sl.rtview.sub=$ocmRowExpirationTime:25
sl.rtview.sub=$ocmRowExpirationTimeForDelete:25
Where:
$ocmRowExpirationMode is 1
$ocmRowExpirationTime is 2.5 times the jmxsampleperiod in seconds
$ocmRowExpirationTimeForDelete is ignored in this mode
Example Mode 3: Expired nodes shown and selectable in displays for a specified time
sl.rtview.sub=$ocmRowExpirationMode:3
sl.rtview.sub=$ocmRowExpirationTime:25
sl.rtview.sub=$ocmRowExpirationTimeForDelete:86400
Where:
$ocmRowExpirationMode is 3
$ocmRowExpirationTime is 2.5 times the jmxsampleperiod in seconds
$ocmRowExpirationTimeForDelete is the amount of time, in milliseconds, expired nodes are displayed. This value must be longer than $ocmRowExpirationTime. A value of 86400 would display expired nodes for 24 hours.
It is helpful to understand jmxsampleperiod property when configuring node expiration modes. jmxsampleperiod is a property used to control the rate at which JMX MBean attributes are polled. It can be used to balance the overhead of requesting the data, with the latency of the results. To avoid overloading systems, request data at a rate no faster than it can be produced by the system being monitored. See the Metrics Administration display to see the total time taken to obtain the JMX data.
The jmxsampleperiod property specifies the time interval, in milliseconds, for polling MBean attributes and operations executed in data attachments if no poll interval is specified in the data attachment. The default is 10000 (10 seconds). This attribute is specified in the rtview.properties file, located in the Monitor projects/mysample directory.
Because the Default Poll Interval is superseded by the General Update Period, the amount of time elapsed between MBean polls might be longer than the value entered. For example, if the General Update Period is 2000 milliseconds and the Default Poll Interval is 5000 milliseconds, MBean attributes and operations are polled every six seconds.