Terminology
Db2 Query Monitor includes several unique terms that you should understand before you begin to use Db2 Query Monitor.
General terminology
- collection point
- A subset of information that Db2 Query
Monitor
collects about the Db2
subsystems it monitors. Db2 Query
Monitor stores data for
each collection point in a corresponding Performance History File.
Table 1. Db2 Query Monitor collection points and their corresponding Performance History Files and offload tables Collection point Performance History File Offload table Db2 commands DB2CDATA CQM_DB2_COMMANDS SQL text TEXTDATA CQM_SUMM_TEXT SQL metrics METRDATA CQM_SUMM_METRICS Db2 objects OBJSDATA CQM_SUMM_OBJECTS Exceptions EXCPDATA CQM_EXCEPTIONS Statement-level exceptions EXCPINDX CQM_EXCP_CALLS SQLCODES SQLCDATA CQM_SQLCODES Exception host variables EXCPHSTV CQM_EXCP_HOSTV Exception SQL text EXCPTEXT CQM_EXCP_TEXT - exception
- A type of event that occurs when an exception threshold (defined in monitoring profiles) is exceeded. An exception is an SQL event that a database administrator might be requested to research.
- interval
- A unit into which Db2 Query Monitor divides and stores data. Intervals have a start time, an end time, an interval number, and other information that uniquely identifies the interval. Data collected by Db2 Query Monitor is stored in performance history files on the mainframe on a per-interval basis.
- monitoring agent
- The interface that Db2 Query Monitor installs within a Db2 subsystem to capture SQL performance data. When a Query Monitor Subsystem collects data about a Db2 subsystem, a monitoring agent is at work collecting data about that Db2 subsystem.
- monitoring profile
- A set of specifications that control how Db2 Query Monitor monitors specific SQL workloads. Monitoring profile control various aspects of monitoring including (but not limited to) summary reporting, SQLCODE reporting, exception limits, exception thresholds, alert limits, alert thresholds, host variable reporting, and OPTKEYS override settings. Monitoring profile do not affect Db2 command reporting. Monitoring profile also enable you to start/stop summary object reporting as well as static and dynamic SQL activity collection for exceptions, SQLCODEs, and summaries.
- monitoring profile line
- A set of specifications that define the inclusion or exclusion of SQL workloads from summary reporting, exception processing, and alert processing. A monitoring profile consist of one or more monitoring profile lines that can be created, inserted, updated, ordered, and deleted as needed to tailor a monitoring profile to fit your needs. Each monitoring profile line applies to one SQL workload.
- Performance History Database
- VSAM data sets that hold metrics, exceptions, and notifications by collection points in Db2 Query Monitor. One Performance History File is created for each collection point, for each interval. Db2 Query Monitor dynamically allocates the Performance History Files. You can control the allocation of Performance History File using parameters specified in CQMPARMS.
- Performance History Files
- VSAM data sets that hold metrics, exceptions, and notifications by collection points in Db2 Query Monitor. One Performance History File is created for each collection point, for each interval. Db2 Query Monitor dynamically allocates the Performance History Files. You can control the allocation of Performance History File using parameters specified in CQMPARMS.
- SQL workload
- A group of applications (and the SQL statements executed by those applications) that is monitored by Db2 Query Monitor to collect performance data. SQL workloads are defined in a monitoring profile. The monitoring profile, in turn, is used by Db2 Query Monitor when monitoring a Db2 subsystem.
- OMEGAMON Data Provider
- OMEGAMON Data Provider (ODP) is a premium functionality that is available within IBM® Db2® Management Solution Pack for z/OS® 3.1, IBM Db2 Performance Solution Pack for z/OS 2.1, any of the IBM Z Systems suites that include OMEGAMON, and with Db2 Query Monitor when acquired as a standalone. This integration helps in streaming data to external analytics platforms, such as IBM Instana, Splunk, Elastic, and Prometheus.
Consolidation and Analysis Engine (CAE) terminology
- action
- A command that can be executed through the CAE Browser Client, either interactively by selecting a domain element and initiating the command, or automatically using a predefined response or action schedule.
- action group
- A set of actions that follow the same action dispatch rule. An action dispatch rule specifies the action agents that are valid for executing a given action for a particular subject.
- alert
- An alert is:
- A type of event that occurs when an alert threshold is exceeded.
- An SQL event for which you want a DBA to stop what they are doing and take immediate action.
- A type of event that occurs due to an SQLCODE or self-event.
- correlation
- In the Alerts Browser, a correlation is a relationship between two events that Db2 Query Monitor interprets as causal in nature. Correlations enable the filtering of related event messages. When one event type is identified as the cause of another event type, the messages for the resulting event type can be subsumed, so that Db2 Query Monitor shows messages for the root cause only.
- domain element
- An element that the CAE models. This includes z/OS® images, Open Systems hosts, Db2 subsystems, SQL statements, Query Monitor Subsystems, CAE Agents, and the Db2 Query Monitor application.
- event
- A condition that occurs when an alert threshold or an exception threshold is exceeded.
Reorganization recommendation terminology
These terms apply to the smarter reorganization recommendation feature. For more information about this feature, see Using smarter reorganization recommendations.
- baseline performance window
- A baseline performance window is an interval (or set of intervals) created by Db2 Query Monitor to which the comparison performance window is compared. The baseline performance window is always older than the comparison performance window. The baseline performance window is newer than the REORG time for the table space.
- comparison performance window
- A comparison performance window is an interval (or set of intervals) that is captured by Db2 Query Monitor and that is compared to the baseline performance window. The comparison performance window is the interval (or set of intervals) for which you want to diagnose a problem, such as decreased performance.
- interval
- An interval is a unit of time into which Db2 Query Monitor divides and stores data. Intervals have a start time, an end time, an interval number, and other information that uniquely identifies the interval. Data collected by Db2 Query Monitor is stored in performance history files on the mainframe on a per-interval basis.
- performance window
- A performance window is a pre-defined time frame during which application performance data is collected for use in determining reorganization recommendations. You should define this time frame as a duration that encompasses execution of the most significant SQL queries that are run on a given Db2 subsystem.
- reorganization recommendation monitor
- The reorganization recommendation monitor is a component of the Db2 Query Monitor CAE Browser Client that enables you to analyze and review performance windows and reorganization recommendations. When you review performance windows, data is shown in the activity browser.