Distribution and consistency services (DCS) stack counters

Distribution and consistency services (DCS) stack counters

You can use the Distribution and Consistency Services (DCS) counters that the Performance Monitoring Infrastructure (PMI) and Tivoli Performance Viewer (TPV) collect to monitor communication between core groups.

Counter definitions

Name Key Description Granularity Type Level Overhead
Number of message buffer reallocations DCSStats.numOfReallocs Number of message buffer reallocations due to inadequate buffer size. If this number is larger than 20 percent of the number of sent messages, you may want to contact IBM Support Per DCS stack CountStatistic All Medium
Outgoing message size DCSStats.outgoingMessageSize Minimal, maximal, and average size (in bytes) of the messages that were sent through the DCS stack Per DCS stack AverageStatistic All High
Number of sent messages DCSStats.outgoingMessageCounter Number of messages sent through the DCS stack Per DCS stack CountStatistic All High
Incoming message size DCSStats.incomingMessageSize Minimal, maximal and average size (in bytes) of the messages that were received by the DCS stack Per DCS stack AverageStatistic All High
Number of received messages DCSStats.incomingMessageCounter Number of messages received by the DCS stack Per DCS stack CountStatistic All High
Amount of time needed for the synchronization procedure to complete DCSStats.vsCompleteCurrentTime Amount of time needed to guarantee that all view members are synchronized. Per DCS stack TimeStatistic All High
Number of messages retransmitted by local member during the view change DCSStats.numOfVSCompletionMessages Number of messages that were retransmitted during the view change to ensure synchronization with other members. Per DCS stack AverageStatistic All High
Number of times that the synchronization procedure timed out DCSStats.vsTimetoutExpiredCounter Number of times that the synchronization procedure timed out. Per DCS stack CountStatistic All Medium
Number of times that a high severity congestion event for outgoing messages was raised DCSStats.transmitterCongestedCounter Number of times that a high severity congestion event for outgoing messages was raised. Per DCS stack CountStatistic All Medium
Number of times the view change procedure timed out. DCSStats.mbrAlarmTimeoutCounter Number of times that membership layer alarms expired, indicating that the view change procedure timed out. Per DCS stack CountStatistic All Medium
Coalesce Time DCSStats.coalesceTime Measures the amount of time it actually takes to coalesce a view. Per DCS stack TimeStatistic All Medium
Join View Change Time DCSStats.mergeTime Measures the time to do a merge view change. The DCS stack is blocked during this time. Per DCS stack TimeStatistic All High
Remove View Change Time DCSStats.splitTime Measures the time to do a split view change.The DCS stack is blocked during this time. Per DCS stack TimeStatistic All High
Number of suspicions DCSStats.suspectCounter Measures the number of times that the local member suspected other members. Per DCS stack CountStatistic All High
Number of view changes DCSStats.viewCounter Number of times that this member underwent view changes. Per DCS stack CountStatistic All Medium
View group size DCSStats.groupSize Measures the size of the group the local member belongs to. Per DCS stack AverageStatistic All1 Medium

Reference topic

Name	Key	Description	Granularity	Type	Level	Overhead
Number of message buffer reallocations	DCSStats.numOfReallocs	Number of message buffer reallocations due to inadequate buffer size. If this number is larger than 20 percent of the number of sent messages, you may want to contact IBM Support	Per DCS stack	CountStatistic	All	Medium
Outgoing message size	DCSStats.outgoingMessageSize	Minimal, maximal, and average size (in bytes) of the messages that were sent through the DCS stack	Per DCS stack	AverageStatistic	All	High
Number of sent messages	DCSStats.outgoingMessageCounter	Number of messages sent through the DCS stack	Per DCS stack	CountStatistic	All	High
Incoming message size	DCSStats.incomingMessageSize	Minimal, maximal and average size (in bytes) of the messages that were received by the DCS stack	Per DCS stack	AverageStatistic	All	High
Number of received messages	DCSStats.incomingMessageCounter	Number of messages received by the DCS stack	Per DCS stack	CountStatistic	All	High
Amount of time needed for the synchronization procedure to complete	DCSStats.vsCompleteCurrentTime	Amount of time needed to guarantee that all view members are synchronized.	Per DCS stack	TimeStatistic	All	High
Number of messages retransmitted by local member during the view change	DCSStats.numOfVSCompletionMessages	Number of messages that were retransmitted during the view change to ensure synchronization with other members.	Per DCS stack	AverageStatistic	All	High
Number of times that the synchronization procedure timed out	DCSStats.vsTimetoutExpiredCounter	Number of times that the synchronization procedure timed out.	Per DCS stack	CountStatistic	All	Medium
Number of times that a high severity congestion event for outgoing messages was raised	DCSStats.transmitterCongestedCounter	Number of times that a high severity congestion event for outgoing messages was raised.	Per DCS stack	CountStatistic	All	Medium
Number of times the view change procedure timed out.	DCSStats.mbrAlarmTimeoutCounter	Number of times that membership layer alarms expired, indicating that the view change procedure timed out.	Per DCS stack	CountStatistic	All	Medium
Coalesce Time	DCSStats.coalesceTime	Measures the amount of time it actually takes to coalesce a view.	Per DCS stack	TimeStatistic	All	Medium
Join View Change Time	DCSStats.mergeTime	Measures the time to do a merge view change. The DCS stack is blocked during this time.	Per DCS stack	TimeStatistic	All	High
Remove View Change Time	DCSStats.splitTime	Measures the time to do a split view change.The DCS stack is blocked during this time.	Per DCS stack	TimeStatistic	All	High
Number of suspicions	DCSStats.suspectCounter	Measures the number of times that the local member suspected other members.	Per DCS stack	CountStatistic	All	High
Number of view changes	DCSStats.viewCounter	Number of times that this member underwent view changes.	Per DCS stack	CountStatistic	All	Medium
View group size	DCSStats.groupSize	Measures the size of the group the local member belongs to.	Per DCS stack	AverageStatistic	All1	Medium