Default workload management objects for concurrency control

For concurrency control, several default workload management objects are created for new or upgraded databases.

Note: This applies if you are not running in an adaptive workload manager environment. To check whether you are running Adaptive Workload Manager environment, see WLM admission control configuration parameter.
  • SYSDEFAULTMANAGEDSUBCLASS, a service subclass under the SYSDEFAULTUSERCLASS service superclass, where heavyweight queries run and can be controlled and monitored as a group
  • SYSDEFAULTCONCURRENT, a CONCURRENTDBCOORDACTIVITIES threshold that is applied to the SYSDEFAULTMANAGEDSUBCLASS subclass to control the number of concurrently running queries that are running in that subclass
  • SYSDEFAULTUSERWCS (a work class set) and SYSMANAGEDQUERIES (a work class), which identify the class of heavyweight queries to control
  • SYSDEFAULTUSERWAS (a work action set) and SYSMAPMANAGEDQUERIES (a work action), which map all queries in the SYSMANAGEDQUERIES work class to the SYSDEFAULTMANAGEDSUBCLASS service subclass

Default managed subclass (SYSDEFAULTMANAGEDSUBCLASS)

You can query the SYSCAT.SERVICECLASSES catalog view to obtain information about the SYSDEFAULTMANAGEDSUBCLASS service subclass. The following table shows the columns, their values, and your ability to modify these values. For information about how to enable or disable the mapping of heavyweight READ DML queries to the SYSDEFAULTMANAGEDSUBCLASS service subclass, see Default query concurrency management.

Table 1. SYSDEFAULTMANAGEDSUBCLASS entry in SYSCAT.SERVICECLASSES view
Column Value Modifiable 1
SERVICECLASSNAME SYSDEFAULTMANAGEDSUBCLASS No
PARENTSERVICECLASSNAME SYSDEFAULTUSERCLASS No
SERVICECLASSID 4 No
PARENTID 3 No
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
ENABLED Y No
AGENTPRIORITY -32768 (default) Yes
PREFETCHPRIORITY ‘ ‘ (default) Yes
MAXDEGREE NULL No
BUFFERPOOLPRIORITY ‘ ‘ (default) Yes
INBOUNDCORRELATOR NULL No
OUTBOUNDCORRELATOR NULL Yes
COLLECTAGGACTDATA N (none) Yes
COLLECTAGGREQDATA N (none) Yes
COLLECTACTDATA N (none) Yes
COLLECTACTPARTITION C (coordinator member of the activity) Yes
COLLECTREQMETRICS N (none) Yes
CPUSHARES 1000 Yes
CPUSHARETYPE H (hard shares) Yes
CPULIMIT -1 (no CPU limit) Yes
SORTMEMORYPRIORITY NULL No
SECTIONACTUALSOPTIONS NN (not enabled) Yes
COLLECTAGGUOWDATA N (none) Yes
REMARKS NULL Yes
Note:
  1. You can modify the value of this column by using the ALTER SERVICE CLASS statement. To issue this statement, DBADM or WLMADM authority and for COLLECT clauses, SQLADM authority is required.

For more information, see SYSCAT.SERVICECLASSES.

Default user work class set (SYSDEFAULTUSERWCS)

You can query the SYSCAT.WORKCLASSSETS catalog view to obtain information about the SYSDEFAULTUSERWCS work class set. The following table shows the columns, their values, and your ability to modify these values. For more information, see Default query concurrency management.

Table 2. SYSDEFAULTUSERWCS entry in SYSCAT.WORKCLASSSETS view
Column Value Modifiable 1
WORKCLASSSETNAME SYSDEFAULTUSERWCS No
WORKCLASSSETID 2147483647 No
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
REMARKS NULL Yes
Note:
  1. You can modify the value of this column by using the ALTER SERVICE CLASS statement. To issue this statement, DBADM or WLMADM authority and for COLLECT clauses, SQLADM authority is required.

For more information, see SYSCAT.WORKCLASSSETS.

Managed queries work class (SYSMANAGEDQUERIES)

You can query the SYSCAT.WORKCLASSES catalog view to obtain information about the SYSMANAGEDQUERIES work class. The following table shows the columns, their values, and your ability to modify these values. For more information, see Default query concurrency management.

Table 3. SYSMANAGEDQUERIES entry in SYSCAT.WORKCLASSES view
Column Value Modifiable 1
WORKCLASSNAME SYSMANAGEDQUERIES No
WORKCLASSSETNAME SYSDEFAULTUSERWCS No
WORKCLASSID 2147483647 No
WORKCLASSSETID 2147483647 No
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
EVALUATIONORDER 1 No
Note:
  1. You can modify the value of this column by using the ALTER SERVICE CLASS statement. To issue this statement, DBADM or WLMADM authority and for COLLECT clauses, SQLADM authority is required.

For more information, see SYSCAT.WORKCLASSES.

You can also query the SYSCAT.WORKCLASSATTRIBUTES catalog view to obtain information about the SYSMANAGEDQUERIES work class. The following tables show the columns, their values, and your ability to modify these values.

Table 4. SYSMANAGEDQUERIES entries in SYSCAT.WORKCLASSATTRIBUTES view. Attribute 1
Column Value Modifiable 1
WORKCLASSNAME SYSMANAGEDQUERIES No
WORKCLASSSETNAME SYSDEFAULTUSERWCS No
WORKCLASSID 2147483647 No
WORKCLASSSETID 2147483647 No
TYPE 1 (work type attribute) No
VALUE1 2 (read activities) No
VALUE2 NULL No
VALUE3 NULL No
Note:
  1. You can modify the value of this column by using the ALTER SERVICE CLASS statement. To issue this statement, DBADM or WLMADM authority and for COLLECT clauses, SQLADM authority is required.
Table 5. SYSMANAGEDQUERIES entries in SYSCAT.WORKCLASSATTRIBUTES view. Attribute 2
Column Value Modifiable 1
WORKCLASSNAME SYSMANAGEDQUERIES No
WORKCLASSSETNAME SYSDEFAULTUSERWCS No
WORKCLASSID 2147483647 No
WORKCLASSSETID 2147483647 No
TYPE 2 (timeron cost attribute) No
VALUE1 Minimum timeron cost, computed at database creation or when the Db2® Configuration Advisor is run Yes
VALUE2 -1 (maximum timeron cost; unbounded) Yes
VALUE3 NULL No
Note:
  1. You can modify the value of this column by using the ALTER SERVICE CLASS statement. To issue this statement, DBADM or WLMADM authority and, for COLLECT clauses, SQLADM authority is required.

For more information, see SYSCAT.WORKCLASSATTRIBUTES.

Default user work action set (SYSDEFAULTUSERWAS)

You can query the SYSCAT.WORKACTIONSETS catalog view to obtain information about the SYSDEFAULTUSERWAS work action set. The following table shows the columns, their values, and your ability to modify these values. For information about how to enable or disable the mapping of heavyweight READ DML queries to the SYSDEFAULTMANAGEDSUBCLASS service subclass, see Default query concurrency management.

Table 6. SYSDEFAULTUSERWAS entry in SYSCAT.WORKACTIONSETS view
Column Value Modifiable 1
ACTIONSETNAME SYSDEFAULTUSERWAS No
ACTIONSETID 2147483647 No
WORKCLASSSETNAME SYSDEFAULTUSERWCS No
WORKCLASSSETID 2147483647 No
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
ENABLED Y Yes
OBJECTTYPE b (work action set applies to service superclass) No
OBJECTNAME SYSDEFAULTUSERCLASS No
OBJECTID 3 (service class ID of SYSDEFAULTUSERCLASS) No
REMARKS NULL Yes
Note:
  1. You can modify the value of this column by using the ALTER WORK ACTION SET statement. To issue this statement, DBADM or WLMADM authority is required.

For more information, see SYSCAT.WORKACTIONSETS.

Managed queries work action (SYSMAPMANAGEDQUERIES)

You can query the SYSCAT.WORKACTIONS catalog view to obtain information about the SYSMAPMANAGEDQUERIES work action. The following table shows the columns, their values, and your ability to modify these values. For more information, see Default query concurrency management.

Table 7. SYSMAPMANAGEDQUERIES entry in SYSCAT.WORKACTIONS view
Column Value Modifiable 1
ACTIONNAME SYSMAPMANAGEDQUERIES No
ACTIONID 2147483647 No
ACTIONSETNAME SYSDEFAULTUSERWAS No
ACTIONSETID 2147483647 No
WORKCLASSNAME SYSMANAGEDQUERIES No
WORKCLASSID 2147483647 No
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
ENABLED Y Yes
ACTIONTYPE M (map activities to service subclass) No
REFOBJECTID 4 (service class ID for SYSDEFAULTMANAGEDSUBCLASS) No
REFOBJECTTYPE NULL No
SECTIONACTUALSOPTIONS NN (not enabled) No
Note:
  1. You can modify the value of this column by using the ALTER WORK ACTION SET statement. To issue this statement, DBADM or WLMADM authority is required.

For more information, see SYSCAT.WORKACTIONS.

Default concurrent threshold (SYSDEFAULTCONCURRENT)

You can query the SYSCAT.THRESHOLDS catalog view to obtain information about the SYSDEFAULTCONCURRENT threshold. The following table shows the columns, their values, and your ability to modify these values. For more information, see Default query concurrency management.

Table 8. SYSDEFAULTCONCURRENT entry in SYSCAT.THRESHOLDS view
Column Value Modifiable 1
THRESHOLDNAME SYSDEFAULTCONCURRENT No
THRESHOLDID 2147483647 No
ORIGIN U (not created by work action) No
THRESHOLDCLASS A (aggregate) No
THRESHOLDPREDICATE CONCDBC (concurrent database coordinator activities) No
THRESHOLDPREDICATEID 90 No
DOMAIN SB (service subclass) No
DOMAINID 4 (service class ID of SYSDEFAULTMANAGEDSUBCLASS) No
ENFORCEMENT D (database) No
QUEUING Y Yes
MAXVALUE Computed at database creation or when the Db2 Configuration Advisor is run, based on the host hardware configuration Yes
DATATAGLIST NULL No
QUEUESIZE -1 (unbounded) Yes
OVERFLOWPERCENT -1 No
COLLECTACTDATA N (none) Yes
COLLECTACTPARTITION C (coordinator member of the activity) Yes
EXECUTION S (stop execution when queue is full) Yes
REMAPSCID 0 No
VIOLATIONRECORDLOGGED NULL No
CHECKINTERVAL -1 No
ENABLED Y Yes
CREATE_TIME Time stamp of database creation or upgrade No
ALTER_TIME Time stamp of the last update of this object No
REMARKS NULL Yes
Note:
  1. You can modify the value of this column by using the ALTER THRESHOLD statement. To issue this statement, DBADM or WLMADM authority and, for COLLECT clauses, SQLADM authority is required.

For more information, see SYSCAT.THRESHOLDS.