Displaying Statistics

The current statistics reflect one hour of activity for the date and time shown. The time is reported according to 24-hour notation, such as 13 for statistics gathered between 1300 (1:00 p.m.) and 1400 (2:00 p.m.).

You also can obtain the statistics by running a query on the SQ_STATISTICS table (in the staging database for the selected agent) using another tool, such as Microsoft Excel. For example, you can issue a query such as SELECT * from SQDR.SQ_STATISTICS, and then save or print the results.

This panel is automatically updated every 15 seconds; however the SQ_STATISTICS table (which is the source of the contents) is updated every two minutes.

All times are in milliseconds.

Note that some of these statistics are applicable only to a Db2 for i source.

Active Replications:  show the current, average, maximum, and total number of active replications. For Db2 for i, this displays the values for the QSQJRN journal in the specified <COLLECTION>. If the collection uses a different journal, the qualified name of the journal appears in the form of SCHEMA.JOURNAL, such as SQDRDEV.SQDR for a journal named SQDR that is installed in the SQDRDEV schema.

T1 Log Entries: indicate the number of records processed during the hour i.e. the count of log/journal entries that the worker has seen during the hour. This value may be higher than the actual available count if the agent needed to re-read records for some reason.

T1 Processing time: For Db2 for i, this indicates the time spent reading journal entries into a user space (*USRSPC) object by the most recent call to retrieve journal entries. Also applicable to Db2 LUW. Not a sum; max/min/avg are also displayed.

T1 Read count: For Db2 for i, this is the number of times journal entries were read into the user space on the DB2 for i host during the hour. Also applicable to Db2 LUW.

T1 Retrieve time: For Db2 for i, this is the time used by the most recent retrieval of the content of the user space to the SQDR Plus agent's memory. Not a sum; max/min/avg are also displayed.

T1 Read KBytes: For Db2 for i, this is the number of kilobytes returned from the user space during the hour. Also applicable to Db2 LUW and Oracle This statistic can be used to understand the bandwidth utilization from the host.

T1 Rollbacks: Number of log/journal entries read to handle rollback or undo conditions.

T1 Total time: The sum of all "T1 Processing time" and "T1 Retrieve time" for the current hour.

T1 Undo Count: Applicable to Oracle.

T1 Wait Time: Applicable to Oracle.

T2 Commit time: The sum of time used to periodically commit ongoing staging activity.

T2 Idle time: The sum of the time that the worker was idle.

T2 Lag time: The difference (in milliseconds) between when changes were made in the source database and when the corresponding change is staged by the agent into the tier 2 database. Max/min/avg are also displayed.

The value is based on a sampling mechanism in which the agent inserts a timestamp marker in the source database (on Db2 for i, this is a user-defined journal entry) and evaluates the time elapsed when it processes that record.

A low value for total lag time indicates that, during the hour for which the statistics were sampled, the Journal Reader was maintaining pace with the database changes, reading the journal and recording the change data with no delays. However, in some cases (when the agent is restarted after being stopped for a long period of time), a lag time of zero may be shown until the agent finishes evaluating its current workload (i.e. when it reaches its timestamp marker).  

T2 Processing time: The sum of all time spent staging incremental changes during the hour. This includes "T1 Total time" and "T2 Commit time". In most cases, the sum of "T2 Processing time" and "T2 Idle time" will represent a full hour. Note that this does not include time used for Add/Delete Subscription or if the agent has been stopped or involved in online/offline operations.

 

Filtering

If you have a large number of statistics, you can filter the display by entering a Component or Statistic name at the top of the display. When entering a Component or Statistic name, standard SQL wildcard operators apply - for instance, % character means match anything, and _ is a substitute for exactly one character. There is an implicit % at the end, and the display is updated immediately.  

For example, if you have subscriptions in libraries ALIB, LIB1, LIB2, and LIB100 - i.e. the Components column displays journals located in those libraries -  entering L in the Components field will immediately filter out ALIB and display only LIB1, LIB2, and LIB100.  Entering LIB1 will display LIB1 and LIB100 (because of the implicit %).  To eliminate the implicit % and terminate the string, enter a period. For example, entering LIB1. will display only LIB1 and not LIB100.