System values: Performance overview
You can use IBM® i performance system values to view and change priority, performance adjustments, and processing values for the system.
To access the performance category of system values from System i® Navigator, select Configuration and Services and then select System Values.
System i Navigator uses descriptive names for system values. The following table provides a quick overview of the performance system values available in System i Navigator (and their counterparts in the character-based interface).
Name in System i Navigator | Description of system value | Name in character-based interface |
---|---|---|
Base memory pool maximum eligible threads | This system value specifies the maximum number of eligible threads for the base memory pool. | QBASACTLVL |
Base memory pool minimum size | This system value specifies the minimum base memory pool. | QBASPOOL |
Communications arbiter jobs at restart | This system value specifies the number of communications arbiter system jobs that are available to process work for controllers and devices. | QCMNARB |
Communications configuration recovery | This system value specifies whether communications recovery attempts are made and how many attempts to take. | QCMNRCYLMT |
Allow background database statistics collection | This system value specifies the types of requests for database file statistics collection that are allowed to be processed by system job QDBFSTCCOL. | QDBFSTCCOL |
Dynamically adjust job priorities of interactive jobs | This system value sets the job priorities of interactive jobs | QDYNPTYADJ |
Dynamically adjust job priorities within priority bands | This system value sets the task scheduling policy. | QDYNPTYSCD |
Lock libraries in a user job's library search list | This system value prevents other jobs from deleting or renaming the libraries in the search list. | QLIBLCKLVL |
Maximum eligible threads | This system value specifies the maximum number of eligible threads. | QMAXACTLVL |
Machine memory pool size | This system value specifies the size of the machine memory pool. | QMCHPOOL |
Available display station pass-through server jobs | This system value specifies the number of pass-through server jobs that are available to process IBM i display station pass-through, System i Access workstation function (WSF), and other 5250 emulation programs on programmable workstations. | QPASTHRSVR |
Automatically adjust memory pools and activity levels | This system value specifies when to automatically adjust memory pools and activity levels. | QPFRADJ |
Parallel processing for queries and indexes | This system value specifies whether to use parallel processing. | QQRYDEGREE |
Database query time limit | This system value sets the time limit for a database query. | QQRYTIMLMT |
Automatically adjust thread resources | This system value specifies whether the system should dynamically make adjustments to the affinity of threads currently running on the system. | QTHDRSCADJ |
Thread affinity | This system value specifies whether secondary threads have affinity to the same group of processors and memory as the initial thread. | QTHDRSCAFN |
Move interactive jobs to base pool at end of time slice | This system value specifies whether to move interactive jobs to the base pool at the end of the time slice. | QTSEPOOL |