Adequate central and expanded storage is vital to achieving good performance with CICS®.
Item | Topic |
---|---|
MVS™ considerations | |
Make CICS nonswappable | Making CICS nonswappable |
Move CICS code to the LPA/ELPA | Using modules in the link pack area (LPA/ELPA) |
VSAM considerations | |
Review the use of Hiperspace™ buffers | Using Hiperspace buffers |
Use VSAM LSR where possible | Using VSAM local shared resources (LSR) |
Review the number of VSAM buffers | Defining VSAM buffer allocations for NSR (INDEXBUFFERS and DATABUFFERS) |
Review the number of VSAM strings | Defining VSAM string settings for NSR (STRINGS) |
Task control considerations | |
Adjust maximum tasks (MXT) | Setting the maximum task specification (MXT) |
Control certain tasks by transaction class | Using transaction classes (MAXACTIVE) to control transactions |
MRO/ISC considerations | |
Implement MVS cross-memory services with MRO | CICS intercommunication facilities and performance: overview |
Implement MVS cross-memory services with shared database programs | |
Use CICS intercommunication facilities | CICS intercommunication facilities and performance: overview |
Database considerations | |
Replace DL/I function shipping with IMS™ DBCTL facility | Setting DBCTL minimum threads (MINTHRD) |
Review use of DB2® buffers and threads | Tuning the CICS DB2 attachment facility: Introduction |
Temporary storage and transient data | |
Reduce temporary storage strings or buffers | Tuning the use of CICS temporary storage (TS) |
Reduce transient data strings or buffers | Optimizing the performance of the CICS transient data (TD) facility |
Journaling | |
Increase activity keypoint frequency (AKPFREQ) value | Setting the activity keypoint frequency (AKPFREQ) |
Terminal, VTAM® and SNA | |
Reduce terminal scan delay | Adjusting the terminal scan delay (ICVTSD) |
Reduce concurrent VTAM inputs | Setting the size of the receive-any pool (RAPOOL) |
Reduce VTAM input message size | Setting the size of receive-any input areas (RAMAX) |
Prioritize transactions | Prioritizing tasks |
Reduce concurrent VTAM logon/logoffs | Limiting the number of concurrent logon/logoff requests (OPNDLIM) |
Applications | |
Use PL/I shared library facilities | Using the PL/I shared library |
Miscellaneous | |
Decrease region exit interval | Tuning the region exit interval (ICV) |
Reduce trace table size | CICS trace: performance considerations |
Use only required CICS recovery facilities | CICS recovery: performance considerations |